Abstract

Single-mode surface-emitting distributed feedback terahertz quantum-cascade lasers operating around 2.9 THz are developed in metal-metal waveguides. A combination of techniques including precise control of phase of reflection at the facets, and use of metal on the sidewalls to eliminate higher-order lateral modes allow robust single-mode operation over a range of approximately 0.35 THz. Single-lobed far-field radiation pattern is obtained using a π phase-shift in center of the second-order Bragg grating. A grating device operating at 2.93 THz lased up to 149 K in pulsed mode and a temperature tuning of 19.7 GHz was observed from 5 K to 147 K. The same device lased up to 78 K in continuous-wave (cw) mode emitting more than 6 mW of cw power at 5 K. In general, maximum temperature of pulsed operation for grating devices was within a few Kelvin of that of multi-mode Fabry-Perot ridge lasers.

© 2007 Optical Society of America

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2006

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

O. Demichel, L. Mahler, T. Losco, C. Mauro, R. Green, A. Tredicucci, J. Xu, F. Beltram, H. E. Beere, D. A. Ritchie, and V. Tamosinuas, "Surface plasmon photonic structures in terahertz quantum cascade lasers," Opt. Express 14, 5335 (2006)
[CrossRef] [PubMed]

M. Schubert and F. Rana, "Analysis of Terahertz Surface Emitting Quantum-Cascade Lasers," IEEE J. Quantum Electron. 42, 257 (2006).
[CrossRef]

2005

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Distributed-feedback terahertz quantum-cascade lasers with laterally corrugated metal waveguides," Opt. Lett. 30, 2909 (2005).
[CrossRef] [PubMed]

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode," Opt. Express 13, 3331 (2005),
[CrossRef] [PubMed]

S. Kohen, B. S. Williams, and Q. Hu, "Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators," J. Appl. Phys. 97, 053106 (2005).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

H.-W. Hübers, S. G. Pavlov, A. D. Semenov, R. Köhler, L. Mahler, A. Tredicucci, H. E. Beere, D. A. Ritchie, and E. H. Linfield, "Terahertz quantum cascade laser as local oscillator in a heterodyne receiver," Opt. Express 13, 5890 (2005).
[CrossRef] [PubMed]

2003

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

2002

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

2001

M. K. Gunde and M. Maček, "Infrared Optical Constants and Dielectric Response Functions of Silicon Nitride and Oxynitride Films," Phys. Stat. Sol.(a) 183, 439 (2001).
[CrossRef]

2000

N. Finger, W. Schrenk, and E. Gornik, "Analysis of TM-polarized DFB laser structures with metal surface gratings," IEEE J. Quantum Electron. 36, 780 (2000).
[CrossRef]

1999

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

1990

R. J. Noll and S. H. Macomber, "Analysis of grating surface emitting lasers," IEEE J. Quantum Electron. 26, 456 (1990).
[CrossRef]

1985

Adam, A. J. L.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Alexander-Jr, R.W.

Austerer, M.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Baryshev, A.

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Baselmans, J. J. A.

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Beck, M.

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

Beere, H.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

Beere, H. E.

Bell, R. J.

Beltram, F.

O. Demichel, L. Mahler, T. Losco, C. Mauro, R. Green, A. Tredicucci, J. Xu, F. Beltram, H. E. Beere, D. A. Ritchie, and V. Tamosinuas, "Surface plasmon photonic structures in terahertz quantum cascade lasers," Opt. Express 14, 5335 (2006)
[CrossRef] [PubMed]

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Botez, D.

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

Callebaut, H.

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

Cockburn, J. W.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Davies, A. G.

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Demichel, O.

Faist, J.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

Finger, N.

N. Finger, W. Schrenk, and E. Gornik, "Analysis of TM-polarized DFB laser structures with metal surface gratings," IEEE J. Quantum Electron. 36, 780 (2000).
[CrossRef]

Gao, J. R.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Golka, S.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Gornik, E.

N. Finger, W. Schrenk, and E. Gornik, "Analysis of TM-polarized DFB laser structures with metal surface gratings," IEEE J. Quantum Electron. 36, 780 (2000).
[CrossRef]

Green, , R. P.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Green, R.

Gunde, M. K.

M. K. Gunde and M. Maček, "Infrared Optical Constants and Dielectric Response Functions of Silicon Nitride and Oxynitride Films," Phys. Stat. Sol.(a) 183, 439 (2001).
[CrossRef]

Hajenius, M.

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Hofstetter, D.

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

Hovenier, J. N.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Hu, Q.

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

S. Kohen, B. S. Williams, and Q. Hu, "Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators," J. Appl. Phys. 97, 053106 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode," Opt. Express 13, 3331 (2005),
[CrossRef] [PubMed]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Distributed-feedback terahertz quantum-cascade lasers with laterally corrugated metal waveguides," Opt. Lett. 30, 2909 (2005).
[CrossRef] [PubMed]

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

Hübers, H.-W.

Iotti, R. C.

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Kaalynas, I.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

Klaassen, T. O.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Klapwijk, T. M.

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Kohen, S.

S. Kohen, B. S. Williams, and Q. Hu, "Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators," J. Appl. Phys. 97, 053106 (2005).
[CrossRef]

Köhler, R.

H.-W. Hübers, S. G. Pavlov, A. D. Semenov, R. Köhler, L. Mahler, A. Tredicucci, H. E. Beere, D. A. Ritchie, and E. H. Linfield, "Terahertz quantum cascade laser as local oscillator in a heterodyne receiver," Opt. Express 13, 5890 (2005).
[CrossRef] [PubMed]

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Krysa, A. B.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Kumar, S.

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode," Opt. Express 13, 3331 (2005),
[CrossRef] [PubMed]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Distributed-feedback terahertz quantum-cascade lasers with laterally corrugated metal waveguides," Opt. Lett. 30, 2909 (2005).
[CrossRef] [PubMed]

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

Lee, A.

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

Li, S.

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

Linfield, E. H.

H.-W. Hübers, S. G. Pavlov, A. D. Semenov, R. Köhler, L. Mahler, A. Tredicucci, H. E. Beere, D. A. Ritchie, and E. H. Linfield, "Terahertz quantum cascade laser as local oscillator in a heterodyne receiver," Opt. Express 13, 5890 (2005).
[CrossRef] [PubMed]

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Losco, T.

Macek, M.

M. K. Gunde and M. Maček, "Infrared Optical Constants and Dielectric Response Functions of Silicon Nitride and Oxynitride Films," Phys. Stat. Sol.(a) 183, 439 (2001).
[CrossRef]

Macomber, S.

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

Macomber, S. H.

R. J. Noll and S. H. Macomber, "Analysis of grating surface emitting lasers," IEEE J. Quantum Electron. 26, 456 (1990).
[CrossRef]

Mahler, L.

Mauro, C.

Noll, R. J.

R. J. Noll and S. H. Macomber, "Analysis of grating surface emitting lasers," IEEE J. Quantum Electron. 26, 456 (1990).
[CrossRef]

Oesterle, U.

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

Ordal, M. A.

Orlova, E. E.

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

Pavlov, S. G.

Pflügl, C.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Qin, Q.

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

Rana, F.

M. Schubert and F. Rana, "Analysis of Terahertz Surface Emitting Quantum-Cascade Lasers," IEEE J. Quantum Electron. 42, 257 (2006).
[CrossRef]

Reno, J. L.

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode," Opt. Express 13, 3331 (2005),
[CrossRef] [PubMed]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Distributed-feedback terahertz quantum-cascade lasers with laterally corrugated metal waveguides," Opt. Lett. 30, 2909 (2005).
[CrossRef] [PubMed]

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

Ritchie, D.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

Ritchie, D. A.

Roberts, J. S.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Rossi, F.

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Scalari, G.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

Schrenk, W.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

N. Finger, W. Schrenk, and E. Gornik, "Analysis of TM-polarized DFB laser structures with metal surface gratings," IEEE J. Quantum Electron. 36, 780 (2000).
[CrossRef]

Schubert, M.

M. Schubert and F. Rana, "Analysis of Terahertz Surface Emitting Quantum-Cascade Lasers," IEEE J. Quantum Electron. 42, 257 (2006).
[CrossRef]

Semenov, A. D.

Strasser, G.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Tamosinuas, V.

Tredicucci, A.

Walther, C.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

Williams, B. S.

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

S. Kohen, B. S. Williams, and Q. Hu, "Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators," J. Appl. Phys. 97, 053106 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode," Opt. Express 13, 3331 (2005),
[CrossRef] [PubMed]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Distributed-feedback terahertz quantum-cascade lasers with laterally corrugated metal waveguides," Opt. Lett. 30, 2909 (2005).
[CrossRef] [PubMed]

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

Wilson, L. R.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Witjaksono, G.

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

Xu, J.

Yang, Z. Q.

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

G. Scalari, C. Walther, J. Faist, H. Beere, and D. Ritchie, "Electrically switchable, two-color quantum cascade laser emitting at 1.39 and 2.3 THz," Appl. Phys. Lett. 88, 141102 (2006).
[CrossRef]

A. Lee, Q. Qin, S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "Real-time terahertz imaging over a standoff distance (> 25 m)," Appl. Phys. Lett. 89, 141125 (2006).
[CrossRef]

J. R. Gao, J. N. Hovenier, Z. Q. Yang, J. J. A. Baselmans, A. Baryshev, M. Hajenius, T. M. Klapwijk, A. J. L. Adam, T. O. Klaassen, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "A terahertz heterodyne receiver based on a quantum cascade laser and a superconducting bolometer," Appl. Phys. Lett. 86, 244104 (2005).
[CrossRef]

B. S. Williams, S. Kumar, H. Callebaut, Q. Hu, and J. L. Reno, "Terahertz quantum-cascade laser at ⌊ ≈ 100 m using metal waveguide for mode confinement," Appl. Phys. Lett. 83, 2124 (2003).
[CrossRef]

A. J. L. Adam, I. Kaalynas, J. N. Hovenier, T. O. Klaassen, J. R. Gao, E. E. Orlova, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Beam patterns of terahertz quantum cascade lasers with subwavelength cavity dimensions," Appl. Phys. Lett. 88, 151105 (2006).
[CrossRef]

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 m quantum cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769 (1999).
[CrossRef]

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Electron. Lett.

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Electron. Lett. 42, 89 (2006).
[CrossRef]

IEEE J. Quantum Electron.

R. J. Noll and S. H. Macomber, "Analysis of grating surface emitting lasers," IEEE J. Quantum Electron. 26, 456 (1990).
[CrossRef]

N. Finger, W. Schrenk, and E. Gornik, "Analysis of TM-polarized DFB laser structures with metal surface gratings," IEEE J. Quantum Electron. 36, 780 (2000).
[CrossRef]

M. Schubert and F. Rana, "Analysis of Terahertz Surface Emitting Quantum-Cascade Lasers," IEEE J. Quantum Electron. 42, 257 (2006).
[CrossRef]

IEEE J. Sel. Top. Quantum Electron.

S. Li, G. Witjaksono, S. Macomber, and D. Botez, "Analysis of surface-emitting second-order distributed feedback lasers with central grating phaseshift," IEEE J. Sel. Top. Quantum Electron. 9, 1153 (2003).
[CrossRef]

IEEE Photon. Technol. Lett.

A. Lee, B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "Real-Time Imaging Using a 4.3-THz Quantum Cascade Laser and a 320 x 240 Microbolometer Focal-Plane Array," IEEE Photon. Technol. Lett. 18, 1415 (2006).
[CrossRef]

J. Appl. Phys.

S. Kohen, B. S. Williams, and Q. Hu, "Electromagnetic modeling of terahertz quantum cascade laser waveguides and resonators," J. Appl. Phys. 97, 053106 (2005).
[CrossRef]

Nature

R. Köhler, A. Tredicucci, F. Beltram, H. E. Beere, E. H. Linfield, A. G. Davies, D. A. Ritchie, R. C. Iotti, and F. Rossi, "Terahertz semiconductor-heterostructure laser," Nature 417, 156 (2002).
[CrossRef] [PubMed]

Opt. Express

Opt. Lett.

Phys. Stat. Sol.

M. K. Gunde and M. Maček, "Infrared Optical Constants and Dielectric Response Functions of Silicon Nitride and Oxynitride Films," Phys. Stat. Sol.(a) 183, 439 (2001).
[CrossRef]

Other

S. Kumar, B. S. Williams, Q. Hu, and J. L. Reno, "First-order edge-emitting and second-order surface-emitting distributed feedback terahertz quantum cascade lasers," presented at the 8th International Conference on Intersubband Transitions in Quantum Wells, Cape Cod, Massachusetts, 11-16 Sept. 2005.

J. Jin, The Finite Element Method in Electromagnetics, 2nd ed. (Wiley-IEEE Press, 2002).

R. Williams, Modern GaAs processing methods, chapter 5, p. 97, 2nd ed. (Artech House, Boston, 1990).

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Figures (12)

Fig. 1.
Fig. 1.

(a) Three dimensional schematic of the grating structure. (b) Electric-field lines for a grating mode showing the grating induced change in field polarization to achieve surface emission. (c),(d) Electric-field profiles for the fundamental propagating mode in an infinitely long, 100 μm wide waveguide with and without top-metal, respectively, at 3 THz. The corresponding propagation mode indices n eff are 3.58 and 2.66 where n GaAs is taken to be 3.6. The aspect ratio for the plotted geometry in the x and y directions is not to scale.

Fig. 2.
Fig. 2.

(a) Mode-spectrum for a finite length (infinite-width) grating structure of the type shown in Fig. 1. Plotted is propagation loss inside the waveguide due to surface out-coupling only. (b),(c) Energy-density averaged along waveguide height for lower and upper band-edge modes plotted along the length. The grey rectangular lines are shown as guides to locate grating apertures. (d),(e) Electric-field profiles near center of grating for lower and upper band-edge modes respectively.

Fig. 3.
Fig. 3.

(a),(b),(c) Grating mode-spectrums and average energy-density plots along waveguide length for the lowest-loss modes corresponding to three different end-lengths. Other grating parameters are the same as in Fig. 2.

Fig. 4.
Fig. 4.

(a) Grating mode spectrum, and vertically averaged Ez plotted along the length with the corresponding far-field radiation pattern for the lower band-edge mode. These are calculated for end-length δ = Λ/2 to show the mode behavior clearly since this δ produces a relatively bigger surface loss. Other grating parameters are the same as in Fig. 2. Ez envelopes are alternately antisymmetric (‘a’) and symmetric (‘s’) along the length for adjacent modes. (b) Same quantities plotted for a similar structure that has a Λ/2 section of waveguide removed from the center to create a -Λ/2 defect in the grating. Consequently, polarities for Ez envelopes are switched from ‘a’ to ‘s’ and vice-versa.

Fig. 5.
Fig. 5.

(a) SEM of a grating device fabricated by dry-etching. (b) Single-mode cw spectrum from one such grating device measured at 5 K. (c) Far-field intensity pattern for the same device measured at a distance of ≈ 2.5 cm with a microbolometer camera [6].

Fig. 6.
Fig. 6.

(a) Grating mode spectrum obtained by three-dimensional simulation of a 12-period grating with Λ = 32 μm, δ = Λ/4 + Λ/8, 90 % duty-cycle, and -Λ/2 defect in center. The cavity facets are covered with metal while the sidewalls are left open. Ridge dimensions are 40 μm × 392 μm × 10 μm. Modes in blue are fundamental lateral modes and the ones in red are second lateral modes. (b) Ey plots in the waveguide for the lower band-edge fundamental lateral mode, and for a second lateral mode close to it in frequency.

Fig. 7.
Fig. 7.

(a),(b) SEMs of a wet-etched GaAs/Al0.15Ga0.85As MQW region grown on a (100) GaAs substrate taken along longitudinal and lateral directions, respectively, of a rectangular mesa. Etch-mask for the mesa was aligned parallel to (110) directions. The bottom surface is GaAs. (c) SEM of a mesa when etch-mask was aligned parallel to (100) directions. The etchant used was H2SO4:H2O2:H2O 1:8:80 and etch-depth was ≈ 10 /im. The bottom surface is metal.

Fig. 8.
Fig. 8.

(a) Energy-density profiles for different lateral modes at 2.9 THz in an 80 μm wide metal-metal waveguide covered with SiO2/Ti/Au on the sidewalls. Calculated propagation loss α due to metal only is indicated. The aspect ratio of the plotted geometry is not to scale. (b) Close-up for the third-lateral mode near the bottom edge of the ridge. (c) Measured cw spectra on log scale at 5 K from two Fabry-Perot ridge lasers with cleaved facets (size 80 μm×0.92 mm) located close to each other on the same die. The two devices are nominally identical except the one without metal on the sidewalls yielded higher-order lateral modes (top, where the mode spacing is nonuniform); while the one with metal on the sidewalls yielded only fundamental lateral mode (bottom).

Fig. 9.
Fig. 9.

SEMs of metal-metal grating devices fabricated with mesas along 〈100〉 directions. The sidewalls and facets are covered with 300/30/350 nm of SiO2/Ti/Au. Al wire bonds are made on bonding pads away from the mesas to electrically bias the lasers. SiO2 isolates the bonding pads from the bottom Ta/Cu.

Fig. 10.
Fig. 10.

(a) 5-K cw spectra for three different grating devices (each color corresponding to a device with different Λ), plotted on log scale. Spectra for different bias are plotted starting from near-threshold bias at bottom to peak-bias at top. Signal recorded from the Λ = 32 μm device, which lased at 2.77 THz, was very weak due to it being on a strong atmospheric water-absorption line. Maximum temperature of pulsed operation are also indicated. (b) CW spectrum from a Fabry-Perot ridge laser that was located adjacent to grating devices on the same die, plotted on linear scale. (c) λ0 versus Λ variation (in solid red). A line going through origin and corresponding to n eff ≈ λ0/Λ = 3.44 is also plotted (in dashed blue).

Fig. 11.
Fig. 11.

(a) Far-field radiation pattern measured from the Λ = 30 μm grating device with a He-cooled Ge:Ga photo-detector at an angular resolution of < 1°, and a distance of 33 cm from the laser. The full-width at half-maximum in the longitudinal (z) direction is ∼ 5°. (b) Real-time snapshot of the radiation pattern at a distance of ∼ 2.5 cm from the laser taken with a room-temperature 320 × 240 element (1.48 × 1.11 cm2)microbolometer camera [6]. Three images taken at different x locations are stacked vertically to show the full image.

Fig. 12.
Fig. 12.

Pulsed (top) and cw (bottom) L-I characteristics measured from the Λ = 30 μm grating device (ridge-size: 65 μm+0.90 mm). The cw I-V measured at 5 K is also plotted. The pulsed data is taken using 200-ns pulses repeated at 10 kHz with a He-cooled Ge:Ga photo-detector, while the cw data is measured with room-temperature pyroelectric detector. The upper panel inset on the left shows temperature tuning of the single-mode spectrum due to change in the active region refractive index from 5 K to 147 K, while the inset on the right shows an expanded version of the L-Is at higher temperatures.

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