Abstract

We report the fabrication and experimental characterization of an ultra-high Q microdisk resonator in a silicon-on-insulator (SOI) platform. We examine the role of the substrate in the performance of such microdisk resonators. While substrate leakage loss has warranted the necessity of substrate undercut structures in the past, we show here that the substrate has a very useful role to play for both passive chip-scale device integration as well as active electronic device integration. Two device architectures for the disk-on-substrate are studied in order to assess the possibility of such an integration of high Q resonators and active components. Using an optimized process for fabrication of such a resonator device, we experimentally demonstrate a Q~3×106, corresponding to a propagation loss ~0.16 dB/cm. This, to our knowledge, is the maximum Q observed for silicon microdisk cavities of this size for disk-on-substrate structures. Critical coupling for a resonance mode with an unloaded Q~0.7×106 is observed. We also report a detailed comparison of the obtained experimental resonance spectrum with the theoretical and simulation analysis. The issue of waveguide-cavity coupling is investigated in detail and the conditions necessary for the existence or lack of critical coupling is elaborated.

© 2007 Optical Society of America

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References

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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  7. A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
  22. T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, "Modal coupling in traveling-wave resonators," Opt. Lett. 27, 1669-1671 (2002).
    [CrossRef]
  23. R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
    [CrossRef]
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2006 (4)

2005 (5)

2004 (5)

V. R. Almeida, C. A. Barrios, R. R. Panepucci, and M. Lipson, "All-optical control of light on a silicon chip," Nature 431, 1081-1084 (2004).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

M. Borselli, K. Srinivasan, P. E. Barclay, and O. Painter, "Rayleigh scattering, mode coupling, and optical loss in silicon microdisks," Appl. Phys. Lett. 85, 3693-3695 (2004).
[CrossRef]

O. Boyraz and B. Jalali, "Demonstration of a silicon Raman laser," Opt. Express 12, 5269-5273 (2004).
[CrossRef] [PubMed]

J. Niehusmann, A. Vörckel, P. H. Bolivar, T. Wahlbrink, W. Henschel, and H. Kurz, "Ultrahigh-quality-factor silicon-on-insulator microring resonator," Opt. Lett.,  29, 2861(2004).
[CrossRef]

2002 (1)

2000 (3)

M. L. Gorodetsky, A. Pryamikov, and V. Ilchenko, "Rayleigh scattering in high-Q microspheres," J. Opt. Soc. Am. B 17, 1051-1057 (2000).
[CrossRef]

A. Yariv, "Universal relations for coupling of optical power between microresonators and dielectric waveguides," Electron. Lett.,  36, 321(2000).
[CrossRef]

M. Cai, O. Painter and K. J. Vahala, "Observation of critical coupling in a fiber taper to silica-microsphere whispering gallery mode system," Phys. Rev. Lett.,  85, 74(2000).
[CrossRef] [PubMed]

1998 (1)

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

1997 (1)

1995 (1)

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

1986 (1)

R. A. Soref and J. P. Lorenzo, "All-Silicon Active and Passive Guided-Wave Components for λ=1.3 and 1.6μm," IEEE J. Quantum Electron. 22,873-879 (1986).
[CrossRef]

Almeida, V. R.

V. R. Almeida, C. A. Barrios, R. R. Panepucci, and M. Lipson, "All-optical control of light on a silicon chip," Nature 431, 1081-1084 (2004).
[CrossRef] [PubMed]

Barclay, P. E.

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

M. Borselli, K. Srinivasan, P. E. Barclay, and O. Painter, "Rayleigh scattering, mode coupling, and optical loss in silicon microdisks," Appl. Phys. Lett. 85, 3693-3695 (2004).
[CrossRef]

Barrios, C. A.

V. R. Almeida, C. A. Barrios, R. R. Panepucci, and M. Lipson, "All-optical control of light on a silicon chip," Nature 431, 1081-1084 (2004).
[CrossRef] [PubMed]

Bolivar, P. H.

Borselli, M.

Boyraz, O.

Cai, M.

M. Cai, O. Painter and K. J. Vahala, "Observation of critical coupling in a fiber taper to silica-microsphere whispering gallery mode system," Phys. Rev. Lett.,  85, 74(2000).
[CrossRef] [PubMed]

Chu, S. T.

Cohen, O.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Emelett, S. J.

Fang, A.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

Gorodetsky, M. L.

Hak, D.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

Hare, J.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Haroche, S.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Henschel, W.

Hoekstra, R. J.

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

Ilchenko, V.

Jalali, B.

Johnson, T. J.

Jones, R.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Kippenberg, T. J.

Kurz, H.

Kushner, M. J.

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

Laine, J.-P.

Lef’evre-Seguin, V.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Lev, B.

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

Liao, L.

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Lipson, M.

Little, B. E.

Liu, A.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Lorenzo, J. P.

R. A. Soref and J. P. Lorenzo, "All-Silicon Active and Passive Guided-Wave Components for λ=1.3 and 1.6μm," IEEE J. Quantum Electron. 22,873-879 (1986).
[CrossRef]

Mabuchi, H.

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

Nicolaescu, R.

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Niehusmann, J.

Painter, O.

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

T. J. Johnson, M. Borselli, and O. Painter, "Self-induced optical modulation of the transmission through a high-Q silicon microdisk resonator," Opt. Express,  14, 817-831(2006).
[CrossRef] [PubMed]

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]

M. Borselli, K. Srinivasan, P. E. Barclay, and O. Painter, "Rayleigh scattering, mode coupling, and optical loss in silicon microdisks," Appl. Phys. Lett. 85, 3693-3695 (2004).
[CrossRef]

M. Cai, O. Painter and K. J. Vahala, "Observation of critical coupling in a fiber taper to silica-microsphere whispering gallery mode system," Phys. Rev. Lett.,  85, 74(2000).
[CrossRef] [PubMed]

Panepucci, R. R.

V. R. Almeida, C. A. Barrios, R. R. Panepucci, and M. Lipson, "All-optical control of light on a silicon chip," Nature 431, 1081-1084 (2004).
[CrossRef] [PubMed]

Paniccia, M.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Poon, A. W.

Preble, S. F.

Pryamikov, A.

Raimond, J.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Rong, H.

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

Rubin, D.

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Samara-Rubio, D.

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

Sandoghdar, V.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Schmidt, B. S.

Schoenborn, P.

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

Sekaric, L.

Soref, R. A.

S. J. Emelett and R. A. Soref, "Design and simulation of silicon microring optical routing switches," J. Lightwave Technol.,  23,1800-1807 (2005).
[CrossRef]

R. A. Soref and J. P. Lorenzo, "All-Silicon Active and Passive Guided-Wave Components for λ=1.3 and 1.6μm," IEEE J. Quantum Electron. 22,873-879 (1986).
[CrossRef]

Spillane, S. M.

Srinivasan, K.

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

M. Borselli, K. Srinivasan, P. E. Barclay, and O. Painter, "Rayleigh scattering, mode coupling, and optical loss in silicon microdisks," Appl. Phys. Lett. 85, 3693-3695 (2004).
[CrossRef]

Sukharev, V.

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

Vahala, K. J.

T. J. Kippenberg, S. M. Spillane, and K. J. Vahala, "Modal coupling in traveling-wave resonators," Opt. Lett. 27, 1669-1671 (2002).
[CrossRef]

M. Cai, O. Painter and K. J. Vahala, "Observation of critical coupling in a fiber taper to silica-microsphere whispering gallery mode system," Phys. Rev. Lett.,  85, 74(2000).
[CrossRef] [PubMed]

Vlasov, Y. A.

Vörckel, A.

Wahlbrink, T.

Weiss, D.

D. Weiss, V. Sandoghdar, J. Hare, V. Lef’evre-Seguin, J. Raimond, and S. Haroche, "Splitting of high-Q Mie modes induced by light backscattering in silica microspheres," Opt. Lett. 22, 1835 (1995).
[CrossRef]

Xia, F.

Xu, Q.

Yariv, A.

A. Yariv, "Universal relations for coupling of optical power between microresonators and dielectric waveguides," Electron. Lett.,  36, 321(2000).
[CrossRef]

Zhou, L.

Appl. Phys. Lett. (2)

M. Borselli, K. Srinivasan, P. E. Barclay, and O. Painter, "Rayleigh scattering, mode coupling, and optical loss in silicon microdisks," Appl. Phys. Lett. 85, 3693-3695 (2004).
[CrossRef]

P. E. Barclay, K. Srinivasan, O. Painter, B. Lev, and H. Mabuchi "Integration of fiber coupled high-Q SiNx microdisks with atom chips", Appl. Phys. Lett.,  89,131108(2006).
[CrossRef]

Electron. Lett. (1)

A. Yariv, "Universal relations for coupling of optical power between microresonators and dielectric waveguides," Electron. Lett.,  36, 321(2000).
[CrossRef]

IEEE J. Quantum Electron. (1)

R. A. Soref and J. P. Lorenzo, "All-Silicon Active and Passive Guided-Wave Components for λ=1.3 and 1.6μm," IEEE J. Quantum Electron. 22,873-879 (1986).
[CrossRef]

J. Lightwave Technol. (2)

J. Opt. Soc. Am. B (1)

J. Vac. Sci. Technol. B (1)

R. J. Hoekstra, M. J. Kushner, V. Sukharev, and P. Schoenborn, "Microtrenching resulting from specular reflection during chlorine etching of silicon," J. Vac. Sci. Technol. B,  16, 2102 (1998).
[CrossRef]

Nature (3)

V. R. Almeida, C. A. Barrios, R. R. Panepucci, and M. Lipson, "All-optical control of light on a silicon chip," Nature 431, 1081-1084 (2004).
[CrossRef] [PubMed]

A. Liu, R. Jones, L. Liao, D. Samara-Rubio, D. Rubin, O. Cohen, R. Nicolaescu, and M. Paniccia, "A high-speed silicon optical modulator based on a metal-oxide-semiconductor capacitor," Nature 427, 615-618 (2004).
[CrossRef] [PubMed]

H. Rong, R. Jones, A. Liu, O. Cohen, D. Hak, A. Fang, and M. Paniccia, "A continuous-wave Raman silicon laser," Nature 433, 725-728 (2005).
[CrossRef] [PubMed]

Opt. Express (5)

Opt. Lett. (5)

Phys. Rev. Lett. (1)

M. Cai, O. Painter and K. J. Vahala, "Observation of critical coupling in a fiber taper to silica-microsphere whispering gallery mode system," Phys. Rev. Lett.,  85, 74(2000).
[CrossRef] [PubMed]

Other (3)

G. T. Reed and A. P. Knights, Silicon Photonics: An Introduction, John Wiley, West Sussex, 2004.
[CrossRef]

L. Pavesi and D. J. Lockwood, Silicon Photonics, Springer-verlag, New York, 2004.

H. Haus, Waves and Fields in Optoelectronics, Prentice-Hall, Englewood Cliffs, New Jersey, 1984.

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Figures (10)

Fig. 1.
Fig. 1.

(a) The cross section of a Si microdisk resonator on oxide substrate, the silicon thickness is 225 nm. (b) The cross section of a pedestal microdisk resonator on oxide substrate; the Si shallow and deep layers have the thicknesses of 60 nm and 225 nm respectively. The energy profile of the fundamental radial TE (electric field predominantly in the plane of the microdisk) mode is shown in the figures. In both cases the disk radius is 20 μm.

Fig. 2.
Fig. 2.

(a) SEM micrograph of a Si microdisk resonator side-coupled to a waveguide; the disk radius is 20 μm and its thickness is 225 nm. The waveguide width is 550 nm and the gap between the disk and the waveguide is 220 nm. (b) A closer view of the structure at the waveguide-cavity coupling region. (c) Sidewall of the microdisk captured at an azimuth angle 30° and sample tilt angle 30°.

Fig. 3.
Fig. 3.

(a) Spectrum of the microdisk resonator shown in Fig. 2 for TE polarization. (b) An ultra-high Q=2×106 was observed at λ=1520.188 nm. From the simulation results, this resonance wavelength corresponds to a 2nd radial order mode with azimuthal number m=218 and an FSR of 5.1 nm. The mode order and FSR are found by comparing the experimental results with the theoretical simulation (which agree very well with the experimental data)

Fig. 4.
Fig. 4.

Observation of resonance mode splitting at resonance λ=1533.642 nm for the microdisk shown in Fig. 2.

Fig. 5.
Fig. 5.

SEM cross section of the pedestal type structure captured at a sample tilt angle of 30°. The microdisk radius and thickness are 20 μm and 225 nm respectively, and the thickness of the shallow pedestal layer is 65 nm.

Fig. 6.
Fig. 6.

(a) Spectrum of the pedestal microdisk resonator coupled to a waveguide for TE polarization. (b) Spectrum of the 2nd order radial mode; mode-splitting due to the coupling of CW and CCW is observed. The theoretical Lorentzian spectrum, which is shown as the solid red curve in Fig. 6(b), resulted in unloaded Qs in agreement with the experimental Qs. The disk radius and the input/output coupling waveguide are identical to the conventional microdisk shown in Fig. 2.

Fig. 7.
Fig. 7.

(a) Graphical representation of the coupling between a waveguide and a microdisk resonator. (b) Power transmission through the waveguide versus normalized loaded quality factor (QL /Q0 ).

Fig. 8.
Fig. 8.

(a) Comparison of the effective indices of the traveling TE modes of the microdisk resonator shown in Fig. 2 for different radial mode orders with that for the waveguide. The dimension of the disk radius and the waveguide is given in the caption of Fig. 2. (b) Qc for different gaps between the waveguide and the microdisk calculated using coupled mode theory

Fig. 9.
Fig. 9.

(a) Comparison of the effective indices of the traveling TE modes of the microdisk resonator with radius of 10μm with that for the waveguide. The dimensions of the waveguide are given in the caption of Fig. 2. (b) Qc for different gaps between the waveguide and the microdisk.

Fig. 10.
Fig. 10.

(a) Experimental observation of critical coupling for the 4th order radial mode of the conventional microdisk shown in Fig. 2 The coupling of about 99% of the power into the cavity is clear. Also, the measured unloaded Q is about 0.7×106.

Equations (2)

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T ( ω 0 ) = P out P in = 1 Q 0 Q c 1 + Q 0 Q c 2
Q L 1 = Q 0 1 + Q c 1

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