Abstract

Microresonator devices which posses ultra-high quality factors are essential for fundamental investigations and applications. Microsphere and microtoroid resonators support remarkably high Q’s at optical frequencies, while planarity constrains preclude their integration into functional lightwave circuits. Conventional semiconductor processing can also be used to realize ultra-high-Q’s with planar wedge-resonators. Still, their full integration with side-coupled dielectric waveguides remains an issue. Here we show the full monolithic integration of a wedge-resonator/waveguide vertically-coupled system on a silicon chip. In this approach the cavity and the waveguide lay in different planes. This permits to realize the shallow-angle wedge while the waveguide remains intact, allowing therefore to engineer a coupling of arbitrary strength between these two. The precise size-control and the robustness against post-processing operation due to its monolithic integration makes this system a prominent platform for industrial-scale integration of ultra-high-Q devices into planar lightwave chips.

© 2012 OSA

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  1. T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
    [CrossRef] [PubMed]
  2. P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
    [CrossRef]
  3. P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
    [CrossRef]
  4. T. J. Kippenberg and K. J. Vahala, “Cavity Optomechanics: Back-Action at the Mesoscale,” Science 321, 1172 (2008).
    [CrossRef] [PubMed]
  5. J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
    [CrossRef]
  6. A. B. Matsko, Practical Applications of Microresonators in Optics and Photonics (CRC Press, 2009).
    [CrossRef]
  7. P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
    [CrossRef]
  8. Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
    [CrossRef]
  9. D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
    [CrossRef]
  10. L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
    [CrossRef]
  11. A. R. Johnson, Y. Okawachi, J. S. Levy, J. Cardenas, K. Saha, M. Lipson, and A. L. Gaeta, “Chip-based frequency combs with sub-100 GHz repetition rates,” Opt. Lett. 37, 875–877 (2012).
    [CrossRef] [PubMed]
  12. A. Gondarenko, J. S. Levy, and M. Lipson, “High confinement micron-scale silicon nitride high Q ring resonator,” Opt. Express 17, 11366–11370 (2009).
    [CrossRef] [PubMed]
  13. G. S. Murugan, J. S. Wilkinson, and M. N. Zervas, “Optical excitation and probing of whispering gallery modes in bottle microresonators: potential for all-fiber add-drop filters,” Opt. Lett. 35, 1893–1895, (2010).
    [CrossRef] [PubMed]
  14. L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
    [CrossRef]
  15. F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
    [CrossRef]
  16. N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
    [CrossRef]
  17. D. W. Vernooy, V. S Ilchenko, H. Mabuchi, E. W. Streed, and H. J. Kimble, “High-Q measurements of fused-silica microspheres in the near infrared,” Opt. Lett. 23, 247–249 (1998).
    [CrossRef]
  18. D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
    [CrossRef] [PubMed]
  19. T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
    [CrossRef]
  20. T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
    [CrossRef]
  21. H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
    [CrossRef]
  22. M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
    [CrossRef]
  23. M. Borselli, T. J. Johnson, and O. Painter, “Beyond the Rayleigh scattering limit in high-Q silicon microdisks: theory and experiment,” Opt. Express 13, 1515–1530 (2005).
    [CrossRef] [PubMed]
  24. N. C. Frateschi and A. F. J. Levi, “The spectrum of microdisk lasers,” J. Appl. Phys. 80, 644–653 (1996).
    [CrossRef]

2012

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

A. R. Johnson, Y. Okawachi, J. S. Levy, J. Cardenas, K. Saha, M. Lipson, and A. L. Gaeta, “Chip-based frequency combs with sub-100 GHz repetition rates,” Opt. Lett. 37, 875–877 (2012).
[CrossRef] [PubMed]

2011

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

2010

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

G. S. Murugan, J. S. Wilkinson, and M. N. Zervas, “Optical excitation and probing of whispering gallery modes in bottle microresonators: potential for all-fiber add-drop filters,” Opt. Lett. 35, 1893–1895, (2010).
[CrossRef] [PubMed]

2009

A. Gondarenko, J. S. Levy, and M. Lipson, “High confinement micron-scale silicon nitride high Q ring resonator,” Opt. Express 17, 11366–11370 (2009).
[CrossRef] [PubMed]

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

2008

T. J. Kippenberg and K. J. Vahala, “Cavity Optomechanics: Back-Action at the Mesoscale,” Science 321, 1172 (2008).
[CrossRef] [PubMed]

2007

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

2006

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

2005

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

M. Borselli, T. J. Johnson, and O. Painter, “Beyond the Rayleigh scattering limit in high-Q silicon microdisks: theory and experiment,” Opt. Express 13, 1515–1530 (2005).
[CrossRef] [PubMed]

2003

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

2002

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

2000

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

1998

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

D. W. Vernooy, V. S Ilchenko, H. Mabuchi, E. W. Streed, and H. J. Kimble, “High-Q measurements of fused-silica microspheres in the near infrared,” Opt. Lett. 23, 247–249 (1998).
[CrossRef]

1996

N. C. Frateschi and A. F. J. Levi, “The spectrum of microdisk lasers,” J. Appl. Phys. 80, 644–653 (1996).
[CrossRef]

Aoki, T.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Arcizet, O.

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Armani, D. K.

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

Arnold, S.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

Baets, R.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Becher, C.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Borselli, M.

Bowen, W. P.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Braun, D.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

Cardenas, J.

Chen, D.-R.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Chen, T.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

Chu, S.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Dayan, B.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

de Vries, T.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

DelHaye, P.

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Duchesne, D.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Fan, X.

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

Ferrera, M.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Frateschi, N. C.

N. C. Frateschi and A. F. J. Levi, “The spectrum of microdisk lasers,” J. Appl. Phys. 80, 644–653 (1996).
[CrossRef]

Furusawa, A.

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Gaeta, A. L.

Geluk, E.-J.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Georgiades, N.

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Ghulinyan, M.

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

Gondarenko, A.

Guider, R.

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

Hanumegowda, N. M.

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

He, L.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Holzwarth, R.

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Hong, T.

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

Hu, E.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Huybrechts, K.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Ilchenko, V.

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Ilchenko, V. S

Imamoglu, A.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Ippen, E. P

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

Jeon, S.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

Johnson, A. R.

Johnson, T. J.

Kalkman, J.

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

Khoshsima, M.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

Kimble, H.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Kimble, H. J.

Kippenberg, T.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Kippenberg, T. J.

T. J. Kippenberg and K. J. Vahala, “Cavity Optomechanics: Back-Action at the Mesoscale,” Science 321, 1172 (2008).
[CrossRef] [PubMed]

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

Kiraz, A.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Kumar, R.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Lee, H.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

Levi, A. F. J.

N. C. Frateschi and A. F. J. Levi, “The spectrum of microdisk lasers,” J. Appl. Phys. 80, 644–653 (1996).
[CrossRef]

Levy, J. S.

Li, J.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

Li, L.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Libchaber, A.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

Lipson, M.

Little, B. E.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Liu, L.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Liu, V.

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

Mabuchi, H.

Matsko, A. B.

A. B. Matsko, Practical Applications of Microresonators in Optics and Photonics (CRC Press, 2009).
[CrossRef]

Michler, P.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Morandotti, R.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Morthier, G.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Moss, D. J.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Murugan, G. S.

Okawachi, Y.

Ozdemir, S. K.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Painter, O.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

M. Borselli, T. J. Johnson, and O. Painter, “Beyond the Rayleigh scattering limit in high-Q silicon microdisks: theory and experiment,” Opt. Express 13, 1515–1530 (2005).
[CrossRef] [PubMed]

Parkins, A.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Patel, B. C.

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

Pavesi, L.

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

Polman, A.

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

Popovic, M. A.

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

Pucker, G.

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

Rakich, P. T.

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

Razzari, L.

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

Regreny, P.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Roelkens, G.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Saha, K.

Scherer, A.

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

Schliesser, A.

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Soljacic, M.

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

Spillane, S. M.

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

Spuesens, T.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Stica, C. J.

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

Streed, E. W.

Teraoka, I.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

Vahala, K.

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Vahala, K. J.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

T. J. Kippenberg and K. J. Vahala, “Cavity Optomechanics: Back-Action at the Mesoscale,” Science 321, 1172 (2008).
[CrossRef] [PubMed]

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

Van Thourhout, D.

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

Vernooy, D.

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Vernooy, D. W.

Vollmer, F.

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

White, I.

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

Wilcut, E.

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

Wilken, T.

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

Wilkinson, J. S.

Xiao, Y.-F.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Yang, K. Y.

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

Yang, L.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

Zervas, M. N.

Zhang, L.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Zhang, Zh.

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

Zhu, J.

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Appl. Phys. Lett.

P. Michler, A. Kiraz, L. Zhang, C. Becher, E. Hu, and A. Imamoglu, “Laser emission from quantum dots in microdisk structures,” Appl. Phys. Lett. 77, 184–186 (2000).
[CrossRef]

Zh. Zhang, L. Yang, V. Liu, T. Hong, K. Vahala, and A. Scherer, “Visible submicron microdisk lasers,” Appl. Phys. Lett. 90, 111119 (2007).
[CrossRef]

F. Vollmer, D. Braun, A. Libchaber, M. Khoshsima, I. Teraoka, and S. Arnold, “Protein detection by optical shift of a resonant microcavity,” Appl. Phys. Lett. 80, 4057–4059 (2002).
[CrossRef]

N. M. Hanumegowda, C. J. Stica, B. C. Patel, I. White, and X. Fan, “Refractometric sensors based on microsphere resonators,” Appl. Phys. Lett. 87, 201107 (2005).
[CrossRef]

T. J. Kippenberg, S. M. Spillane, D. K. Armani, and K. J. Vahala, “Fabrication and coupling to planar high-Q silica disk microcavities,” Appl. Phys. Lett. 83, 797–799 (2003).
[CrossRef]

IEEE Photon. Technol. Lett.

M. Ghulinyan, R. Guider, G. Pucker, and L. Pavesi, “Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides,” IEEE Photon. Technol. Lett. 23, 1166–1168 (2011).
[CrossRef]

J. Appl. Phys.

N. C. Frateschi and A. F. J. Levi, “The spectrum of microdisk lasers,” J. Appl. Phys. 80, 644–653 (1996).
[CrossRef]

Nat. Photonics

H. Lee, T. Chen, J. Li, K. Y. Yang, S. Jeon, O. Painter, and K. J. Vahala, “Chemically etched ultrahigh-Q wedge-resonator on a silicon chip,” Nat. Photonics 6, 369–373 (2012).
[CrossRef]

L. Razzari, D. Duchesne, M. Ferrera, R. Morandotti, S. Chu, B. E. Little, and D. J. Moss, “CMOS-compatible integrated optical hyper-parametric oscillator,” Nat. Photonics 4, 41–45 (2009).
[CrossRef]

L. Liu, R. Kumar, K. Huybrechts, T. Spuesens, G. Roelkens, E.-J. Geluk, T. de Vries, P. Regreny, D. Van Thourhout, R. Baets, and G. Morthier, “An ultra-small, low-power, all-optical flip-flop memory on a silicon chip,” Nat. Photonics 4, 182–187 (2010).
[CrossRef]

P. T. Rakich, M. A. Popovic, M. Soljačic, and E. P Ippen, “Trapping, corralling and spectral bonding of optical resonances through optically induced potentials,” Nat. Photonics 1, 658–665 (2007).
[CrossRef]

J. Zhu, S. K. Ozdemir, Y.-F. Xiao, L. Li, L. He, D.-R. Chen, and L. Yang, “On-chip single nanoparticle detection and sizing by mode splitting in an ultrahigh-Q microresonator,” Nat. Photonics 4, 46–49 (2010).
[CrossRef]

Nature

P. DelHaye, A. Schliesser, O. Arcizet, T. Wilken, R. Holzwarth, and T. J. Kippenberg, “Optical frequency comb generation from a monolithic microresonator,” Nature 450, 1214–1217 (2007).
[CrossRef]

T. Aoki, B. Dayan, E. Wilcut, W. P. Bowen, A. Parkins, T. Kippenberg, K. Vahala, and H. Kimble, “Observation of strong coupling between one atom and a monolithic microresonator,” Nature 443, 671–674 (2006).
[CrossRef] [PubMed]

D. K. Armani, T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, “Ultra-high-Q toroid microcavity on a chip,” Nature 421, 925–928 (2003).
[CrossRef] [PubMed]

Opt. Express

Opt. Lett.

Phys. Rev. A

T. J. Kippenberg, J. Kalkman, A. Polman, and K. J. Vahala, “Demonstration of an erbium-doped microdisk laser on a silicon chip,” Phys. Rev. A 74, 051802 (2006).
[CrossRef]

D. Vernooy, A. Furusawa, N. Georgiades, V. Ilchenko, and H. Kimble, “Cavity QED with high-Q whispering gallery modes,” Phys. Rev. A 57, 2293–2296 (1998).
[CrossRef]

Science

T. J. Kippenberg and K. J. Vahala, “Cavity Optomechanics: Back-Action at the Mesoscale,” Science 321, 1172 (2008).
[CrossRef] [PubMed]

Other

A. B. Matsko, Practical Applications of Microresonators in Optics and Photonics (CRC Press, 2009).
[CrossRef]

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Figures (5)

Fig. 1
Fig. 1

Evanescent field coupling schemes in integrated photonics. (a) A nanometric gap, d1, between a microdisk resonator and a dielectric waveguide defines a side-coupling rate of γ1 ∼ exp(−d1). (b) Such coupling becomes increasingly inefficient when the pre-defined cavity/waveguide distance, d2, increases during the formation of the shallow-angle wedge. In a realistic fabrication process also the waveguide retracts forming a wedge-shape (the dashed inclined line), thus, quenching completely the coupling. Because of this, typically, an off-chip technique (tapered-fiber) is used. (c) The vertical coupling allows for both engineering arbitrarily the evanescent field coupling by controlling the vertical gap, dv, and aligning horizontally the waveguide to the resonator mode. (d) More importantly, this configuration enables the integrated photonics technology to access UHQ wedge resonators with buried dielectric waveguides. The vertical coupling scheme, in fact, permits to realize independently the wedge resonator, maintaining an appropriate coupling rate, γv ∼ exp(−dv). It allows for a direct access of devices through integrated waveguides and has the flexibility to engineer free-standing devices [22].

Fig. 2
Fig. 2

Fully integrated wedge and conventional microdisk resonators with vertical coupling to bus waveguides on a silicon chip. (a,b) Top-view optical images of the resonators. (a) Concentric Newton’s rings of different color at the edge of the wedge resonator indicate to a gradually decreasing layer thickness towards the outer rim. (b) A homogeneous color is observed across the entire disk surface of the dry-etched resonator. Panels (c) and (d) show the bird’s-eye-view SEM images of the wet- and dry-etched devices, respectively. The calculated intensities of first and second-order radial modes for both (e,f) the wedge and (g,h) the disk resonators around the wavelength of 1575 nm are shown. These panels illustrate how the wedge resonator modes are pushed away from the device external periphery into an ≈ 2.2 μm smaller effective radius trajectory due to the shallow-angled (θ ∼ 7°) confining wedge.

Fig. 3
Fig. 3

The schematics of a typical process flow for the realization of vertically coupled wedge resonator/waveguide system. (a) An oxynitride (SiON) layer is deposited in a PECVD chamber on top of a thermally grown silica cladding. (b) SiON strip waveguides are defined using standard lithographic and reactive ion etching (RIE) techniques and, afterwards, cladded by a doped borophosphosilicate glass (BPSG). (c) A high-degree of planarization is achieved by using a two-cycle BPSG deposition-and-reflow procedure. (d) By using RIE the BPSG thickness is reduced in order to achieve the desired thickness (vertical coupling gap) on top of the SiON waveguide. (e) Silicon nitride layer is deposited using the PECVD technique and (f), finally, the wedge resonator is defined using a wet chemical etch in a buffered HF solution. (g) The cross-sectional sketch of the final device. This technology allows also for the realization of air-suspended wedge resonators. After the definition of the coupling gap, (e*) a sacrificial layer, such as amorphous silicon, is deposited on top of BPSG. (f*) Following the deposition of top SiNx layer and (g*) the definition of the wedge resonator, (h*) the sacrificial layer is partially removed using an isotropic selective etching step (see Ref. [22]).

Fig. 4
Fig. 4

Optical characterization of wedge resonators. (a) The optical spectroscopic setup used for waveguide transmission measurements. (b) The measured broad range spectrum of the wedge resonator shows a series of 1st and 2nd order radial family modes of TE-polarization. Some of the these are labeled as (p, m) according to their radial p and azimuthal m mode numbers. (c) The high-resolution spectra taken around a wavelength of 1576 nm are shown for the wedge (top panel) and the microdisk (bottom panel) resonators. In both cases the 1st radial family mode is critically coupled to the bus waveguide and has a −15 dB transmission. Lorentzian fits to the resonances reveals a an almost fourfold increase in the 1st order mode’s Q for the wedge resonator. (d) The mode Q-factors of both the wedge and dry-etched resonators are compared in a 65 nm range around the wavelength of 1570 nm, showing a three- to fourfold difference for the first order radial families and almost no difference for the second order ones. (e) At a shorter wavelength the wedge resonator’s fundamental mode is split into a doublet due to degeneracy lift-off between clockwise and counter-clockwise propagating modes. A reduction in scattering loss of the wedge device and larger transparency of the SiNx material provide intrinsic Q’s higher than the scattering Qs, allowing for doublet observation. Meanwhile, the stronger scattering in the dry-etched device results into a lossy non-split lineshape.

Fig. 5
Fig. 5

Numerical analysis of mode confinement and intensity profiles. (a) Numerically calculated peak wavelengths of the first (M1) and the second (M2) order radial modes of the wedge resonator show an excellent agreement with the experimentally measured ones. (b) The calculated mode confinement factors are reported both for the wedge and the dry-etched resonators. (c) The horizontal and (d) the vertical profiles (through field maxima) of the first order radial modes of two types of resonators around λ = 1576 nm. In particular, the mode maximum in the wedge resonator is situated at a ∼ 1μm smaller radius with respect to the dry-etched case, therefore, is more isolated form the physical edge of the device. The vertical profiles show an identical confinement in both cases. Panels (e) and (f) show the situation for the second order radial modes. In this case, the mode M2 in the wedge resonator is closely situated near the physical edges of the resonator. Insets in (c) and (e) show a close-up of the intensity profiles at the resonator/air interface.

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