Abstract

Terahertz quantum cascade lasers have been investigated as a turn-key terahertz source for widespread applications. Two lasers were mounted in a small liquid nitrogen-cooled dewar and combined with a sophisticated pulse driver. We present a detailed analysis in respect to current-voltage characteristics, emission wavelengths, polarization, pulse lengths and repetition rates. We have measured the laser power with a germanium photoconductor and compared the results to a Golay detector evaluating potential artifacts. We have studied mode profiles in the far-field which mirror the internal mode structure. Potential applications have been illustrated by imaging optical elements and a simple test object. Video rate room temperature imaging has been demonstrated in concept.

© 2006 Optical Society of America

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    [CrossRef]
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2006 (3)

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Elec. Lett. 42,3331-3339 (2006).
[CrossRef]

C. Worrall, J. Alton, M. Houghton, S. Barbieri, H. E. Beere, D. Ritchie, and C. Sirtori, "Continuous wave operation of a superlattice quantum cascade laser emitting at 2 THz," Opt. Express 14,171-181 (2006), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-14-1-171.
[CrossRef] [PubMed]

2005 (8)

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

M. Yamashita, K. Kawase, C. Otani, T. Kiwa, and M. Tonouchi, "Imaging of large-scale integrated circuits using laser terahertz emission microscopy," Opt. Express 13,115-120 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-1-115.
[CrossRef] [PubMed]

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 13,3331-3339 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-9-3331.
[CrossRef] [PubMed]

H.-W. H¨ubers, 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 13,5890-5896 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-15-5890.
[CrossRef] [PubMed]

S. Barbieri, J. Alton, C. Baker, T. Lo, H. E. Beere, and D. Ritchie, "Imaging with THz quantum cascade lasers using a Schottky diode mixer," Opt. Express 13,6497-6503 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-17-6497.
[CrossRef] [PubMed]

A.W. M. Lee, and Q. Hu, "Real-time, continuous-wave terahertz imaging by use of a microbolometer focal-plane array," Opt. Lett. 30,2563-2565 (2005).
[CrossRef] [PubMed]

C. Baker, I. S. Gregory, M. J. Evans, W. R. Tribe, E. H. Linfield, and M. Missous. "All-optoelectronic terahertz system using low-temperature-grown InGaAs photomixers," Opt. Express 13,9639-9644 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-23-9639.
[CrossRef] [PubMed]

2004 (5)

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Ch. A. Schmuttenmaer, "Exploring Dynamics in the Far-Infrared with Terahertz Spectroscopy," Chem. Rev. 104,1759-1779 (2004).
[CrossRef] [PubMed]

J. Darmo, V. Tamosiunas, G., J. Kröll, K. Unterrainer, M. Beck, M. Giovannini, J. Faist, C. Kremser, and P. Debbage, "Imaging with a Terahertz quantum cascade laser," Opt. Express 12,1879-1884 (2004), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-9-1879.
[CrossRef] [PubMed]

R. Sachs and H. G. Roskos, "Mode Calculations for a Terahertz Quantum Cascade Laser," Opt. Express 12,2062-2069 (2004), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-10-2062.
[CrossRef] [PubMed]

2002 (2)

P. H. Siegel, "Terahertz Technology," IEEE Trans. Microwave Theory Tech.,  MTT-50,910-928 (2002).
[CrossRef]

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 417,156-159 (2002).
[CrossRef] [PubMed]

2001 (1)

1995 (3)

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

F. Keilmann, "FIR microscopy," Infrared Phys. Technol. 36,217-224 (1995).
[CrossRef]

1994 (1)

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Ajili, L.

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

Alton, J.

B¨oke, M.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Baker, C.

Barbieri, S.

Bauer, T.

Beere, H. E.

Beltram, 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 417,156-159 (2002).
[CrossRef] [PubMed]

Bergner, A.

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Br¨undermann, E.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Bründermann, E.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

Capasso, F.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Chamberlin, D. R.

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Cho, A. Y.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Czasch, S.

Darmo, J.

Davies, A. G.

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

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 417,156-159 (2002).
[CrossRef] [PubMed]

Ebbinghaus, S.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Evans, M. J.

Faist, J.

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Fitzgerald, A.

Fowler, J.

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

Giovannini, M.

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

Gregory, I. S.

H¨ubers, H.-W.

Haller, E. E.

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Havenith, M.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Heugen, U.

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Heyden, M.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Hoffmann, M.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Hoffmann, S.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Houghton, M.

Hoyler, N.

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

Hu, Q.

Hutchinson, A. L.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

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 417,156-159 (2002).
[CrossRef] [PubMed]

Iwasaki, T.

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Kawase, K.

Keilmann, F.

F. Keilmann, "FIR microscopy," Infrared Phys. Technol. 36,217-224 (1995).
[CrossRef]

Kira, M.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Kiwa, T.

Koch, S. W.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Köhler, R.

Kumar, S.

Lee, A.W. M.

Linfield, E. H.

H.-W. H¨ubers, 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 13,5890-5896 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-15-5890.
[CrossRef] [PubMed]

C. Baker, I. S. Gregory, M. J. Evans, W. R. Tribe, E. H. Linfield, and M. Missous. "All-optoelectronic terahertz system using low-temperature-grown InGaAs photomixers," Opt. Express 13,9639-9644 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-23-9639.
[CrossRef] [PubMed]

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

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 417,156-159 (2002).
[CrossRef] [PubMed]

Lo, T.

Löffler, T.

Mahler, L.

Matsushima, F.

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Matus, M.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Missous, M.

Moloney, J. V.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Moskalenko, A. S.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Muravjov, A. V.

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

Odashima, H.

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Otani, C.

Pavlov, S. G.

H.-W. H¨ubers, 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 13,5890-5896 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-15-5890.
[CrossRef] [PubMed]

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

Reno, J. L.

Ritchie, D.

Ritchie, D. A.

H.-W. H¨ubers, 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 13,5890-5896 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-15-5890.
[CrossRef] [PubMed]

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

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 417,156-159 (2002).
[CrossRef] [PubMed]

Röser, H. P.

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

Roskos, H. G.

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 417,156-159 (2002).
[CrossRef] [PubMed]

Sachs, R.

Saito, S.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Sakai, K.

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

Scalari, G.

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

Schauer, J.C.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Schmuttenmaer, Ch. A.

Ch. A. Schmuttenmaer, "Exploring Dynamics in the Far-Infrared with Terahertz Spectroscopy," Chem. Rev. 104,1759-1779 (2004).
[CrossRef] [PubMed]

Schr¨ock, K.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Schwaab, G.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Semenov, A. D.

Shastin, V. N.

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

Siebert, K. J.

Siegel, P. H.

P. H. Siegel, "Terahertz Technology," IEEE Trans. Microwave Theory Tech.,  MTT-50,910-928 (2002).
[CrossRef]

Sirtori, C.

Sivco, D. L.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Takagi, K.

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Tamosiunas, V.

Tani, M.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Tonouchi, M.

Tredicucci, A.

Tribe, W. R.

Tsunekawa, S.

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Williams, B. S.

Winter, J.

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Worrall, C.

Yamashita, M.

Appl. Phys. Lett. (3)

S. Hoffmann, M. Hoffmann, E. Br¨undermann, M. Havenith, M. Matus, J. V. Moloney, A. S. Moskalenko, M. Kira, S. W. Koch, S. Saito, K. Sakai, "Four-wave mixing and direct terahertz emission with two-color semiconductor lasers," Appl. Phys. Lett. 84,3585-3587 (2004).
[CrossRef]

L. Ajili, G. Scalari, J. Faist, H. E. Beere, J. Fowler, E. H. Linfield, D. A. Ritchie, and A. G. Davies, "High power quantum cascade lasers operating at λ ≈ 87 μm and 130 μm," Appl. Phys. Lett. 84,3986-3988 (2004).
[CrossRef]

G. Scalari, N. Hoyler, M. Giovannini, and J. Faist, Terahertz bound-to-continuum quantum-cascade lasers based on optical-phonon scattering extraction," Appl. Phys. Lett. 84,3585-3587 (2005).

Chem. Rev. (1)

Ch. A. Schmuttenmaer, "Exploring Dynamics in the Far-Infrared with Terahertz Spectroscopy," Chem. Rev. 104,1759-1779 (2004).
[CrossRef] [PubMed]

Elec. Lett. (1)

B. S. Williams, S. Kumar, Q. Hu, and J. L. Reno, "High-power terahertz quantum-cascade lasers," Elec. Lett. 42,3331-3339 (2006).
[CrossRef]

IEEE Trans. Microwave Theory Tech. (1)

P. H. Siegel, "Terahertz Technology," IEEE Trans. Microwave Theory Tech.,  MTT-50,910-928 (2002).
[CrossRef]

Infrared Phys. Technol. (2)

E. Bründermann, H. P. Röser, A. V. Muravjov, S. G. Pavlov, and V. N. Shastin, "Mode fine structure of the FIR p-Ge Intervalenceband Laser measured by Heterodyne Mixing Spectroscopy with an optically pumped ring gas laser," Infrared Phys. Technol. 36,59-69 (1995).
[CrossRef]

F. Keilmann, "FIR microscopy," Infrared Phys. Technol. 36,217-224 (1995).
[CrossRef]

J. Molecular Structure (1)

F. Matsushima, H. Odashima, T. Iwasaki, S. Tsunekawa, and K. Takagi, "Frequency measurement of pure rotational transitions of H2O from 0.5 to 5 THz," J. Molecular Structure 352/353,371-378 (1995)
[CrossRef]

Nature (1)

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 417,156-159 (2002).
[CrossRef] [PubMed]

Opt. Express (9)

T. Löffler, T. Bauer, K. J. Siebert, H. G. Roskos, A. Fitzgerald, and S. Czasch, "Terahertz dark-field imaging of biomedical tissue," Opt. Express 9,616-621 (2001), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-9-12-616.
[CrossRef] [PubMed]

J. Darmo, V. Tamosiunas, G., J. Kröll, K. Unterrainer, M. Beck, M. Giovannini, J. Faist, C. Kremser, and P. Debbage, "Imaging with a Terahertz quantum cascade laser," Opt. Express 12,1879-1884 (2004), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-9-1879.
[CrossRef] [PubMed]

R. Sachs and H. G. Roskos, "Mode Calculations for a Terahertz Quantum Cascade Laser," Opt. Express 12,2062-2069 (2004), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-10-2062.
[CrossRef] [PubMed]

M. Yamashita, K. Kawase, C. Otani, T. Kiwa, and M. Tonouchi, "Imaging of large-scale integrated circuits using laser terahertz emission microscopy," Opt. Express 13,115-120 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-1-115.
[CrossRef] [PubMed]

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 13,3331-3339 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-9-3331.
[CrossRef] [PubMed]

H.-W. H¨ubers, 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 13,5890-5896 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-15-5890.
[CrossRef] [PubMed]

S. Barbieri, J. Alton, C. Baker, T. Lo, H. E. Beere, and D. Ritchie, "Imaging with THz quantum cascade lasers using a Schottky diode mixer," Opt. Express 13,6497-6503 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-17-6497.
[CrossRef] [PubMed]

C. Baker, I. S. Gregory, M. J. Evans, W. R. Tribe, E. H. Linfield, and M. Missous. "All-optoelectronic terahertz system using low-temperature-grown InGaAs photomixers," Opt. Express 13,9639-9644 (2005), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-23-9639.
[CrossRef] [PubMed]

C. Worrall, J. Alton, M. Houghton, S. Barbieri, H. E. Beere, D. Ritchie, and C. Sirtori, "Continuous wave operation of a superlattice quantum cascade laser emitting at 2 THz," Opt. Express 14,171-181 (2006), http://www.opticsexpress.org/abstract.cfm?URI=OPEX-14-1-171.
[CrossRef] [PubMed]

Opt. Lett. (1)

Plasma Sources Sci. Technol. (1)

S. Ebbinghaus, K. Schröck, J.C. Schauer, E. Bründermann, M. Heyden, G. Schwaab, M. Böke, J. Winter, M. Tani, and M. Havenith, "Terahertz time-domain spectroscopy as a new tool for the characterisation of dusty plasmas," Plasma Sources Sci. Technol. 15,72-77 (2006),
[CrossRef]

Rev. Sci. Instrum. (1)

A. Bergner, U. Heugen, E. Bründermann, G. Schwaab, M. Havenith, D. R. Chamberlin, and E. E. Haller, "New p-Ge THz spectrometer for the study of solutions: THz absorption spectroscopy of water," Rev. Sci. Instrum. 76,06310-999 (2005).
[CrossRef]

Science (1)

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser: a new optical source in the mid-infrared," Science 264,553-556 (1994).
[CrossRef] [PubMed]

Other (3)

E. W. Weisstein, "Winston Cone," http://scienceworld.wolfram.com/physics/WinstonCone.html.

E. E. Haller and E. Bründermann, "Doping of germanium and silicon crystals with non-hydrogenic acceptors for far infrared lasers," U.S. Patent No. 6,011,810 (January 4, 2000).

E. Bründermann, "Widely Tunable Far Infrared Hot Hole Semiconductor Lasers", in Long-wavelength Infrared Semiconductor Lasers, edited by Hong K. Choi (Wiley& Sons, New York, 2004), Chapter 6, pp. 279-350.

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Figures (10)

Fig. 1.
Fig. 1.

Quanta-Tera: LN2 dewar and pulse driver. Note the scale on the base plate. The quartz dewar window has a diameter of 25 mm with a free aperture of 20 mm.

Fig. 2.
Fig. 2.

(a) L1 voltage, current and laser pulse trace versus time detected by the Ge PC. (b) L1 pulse intensity as a function of the voltage pulse length varied from 0 to 300 ns. A linear fit has been overlaid.

Fig. 3.
Fig. 3.

Emission of L1 detected with the Golay detector. Upper row: without filter. Lower row: with black LD-PE filter (a) raw data, image size: 20 mm × 16.5 mm, pixel resolution: 0.25 mm. The images are coded to minimum and maximum values of the color scale. Values in μV correspond to the raw data, (b) image constructed by binning 4 by 4 pixel (c) linear interpolation of binned image back to a pixel size of 0.25 mm.

Fig. 4.
Fig. 4.

(a) Integral of L1 pulse intensity trace normalized to the 1 Hz value. Data measured with a Ge PC as a function of repetition frequency f and electrical power Pel at thermal equilibrium (red squares). Black squares correspond to the Golay detector voltage 100 ms after initiation of the pulses. The pulse trains were modulated by 10 Hz at 50% duty. Blue squares correspond to voltages at thermal equilibrium. The frequency scale has to be doubled for the Golay measurements. (b) Golay voltage as a function of time obtained for 90 kHz pulse trains at 10 Hz modulation.

Fig. 5.
Fig. 5.

The intensity at close proximity, with the I-V-curves and spectra of L1 and L2 in the same intensity scale. Each colored square corresponds to a spectrum in the same color. The upper spectrum (light blue) of L2 has been measured by using a narrower slit. Water absorption lines due to air humidity are indicated for reference.

Fig. 6.
Fig. 6.

Polarization of L1 and L2 measured with a wire grid. The curve indicates an ideal polarized source with an ideal polarizing wire grid. The images indicate the laser ridge and substrate orientation.

Fig. 7.
Fig. 7.

(a) L1 mode profile obtained at a distance D = 9 mm with the Golay cell (f = 90 kHz modulated at f M = 10 Hz). A 1 mm hole aperture in an aluminum foil was used to improve resolution. (b) L1 mode profile at 10 mm with a 1.5 mm hole aperture (f = 20 kHz, f M = 9 Hz). (c) Ge PC measurement of L1 at larger distance showing far-field rotation due to optical elements (256 single pulses averaged). Arrows indicate the beam origins in the substrate and the active region. (d) Ge PC measurement of mode profile of L2 indicating the appearance of two beams (256 pulses, measured area: 60 mm × 60 mm). (e) Integrated mode profiles of L2 illustrating mode expansion for different distances D = 43, 58, 83 and 133 mm colored in black, red, green, and blue respectively. (f) Ge PC measurement of L2 at larger distance (256 pulses).

Fig. 8.
Fig. 8.

(a) Exit aperture image of the Winston cone consisting of 600 × 600 pixel with a pixel size of 5 μm. (b) Line trace of the diagonal dashed white line in (a).

Fig. 9.
Fig. 9.

(a) Mode profile without object I 0(x,y) and inset of L1 orientation. (b) Mode profile as transmitted through the object I(x,y). (c) Transmission: I(x, y)/I 0(x, y). (d) visual image: printed 13 mm ring with writing on Xerox foil glued to a 25 mm mirror mount.

Fig. 10.
Fig. 10.

(a) Detected Golay signal at different modulation frequencies f M . (b) Scan of the entrance aperture of the Golay cell (24 mm square with 0.5 mm step size). A three dimensional view is presented to illustrate the good SNR. Some of the pixel values in front have been set to zero to illustrate the noise floor.

Tables (1)

Tables Icon

Table 1. Laser intensity integral and maximum of L2 versus the distance D between the laser facet and detector surface.

Equations (1)

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4 R ( r in + r out ) ( ( r out r ) R + z 1 R 2 ) + ( ( r + r out ) + 1 R 2 + zR ) 2 = 0

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