Abstract

A characteristic feature of quantum cascade lasers is their unipolar carrier transport. We exploit this feature and realize nominally symmetric active regions for terahertz quantum cascade lasers, which should yield equal performance with either bias polarity. However, symmetric devices exhibit a strongly bias polarity dependent performance due to growth direction asymmetries, making them an ideal tool to study the related scattering mechanisms. In the case of an InGaAs/GaAsSb heterostructure, the pronounced interface asymmetry leads to a significantly better performance with negative bias polarity and can even lead to unidirectionally working devices, although the nominal band structure is symmetric. The results are a direct experimental proof that interface roughness scattering has a major impact on transport/lasing performance.

© 2013 OSA

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  1. B. Williams, “Terahertz quantum-cascade lasers,” Nat. Photonics1(9), 517–525 (2007).
    [CrossRef]
  2. F. Capasso, “High-performance midinfrared quantum cascade lasers,” Opt. Eng.49(11), 111102 (2010).
    [CrossRef]
  3. C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
    [CrossRef] [PubMed]
  4. L. Lever, N. M. Hinchcliffe, S. P. Khanna, P. Dean, Z. Ikonic, C. A. Evans, A. G. Davies, P. Harrison, E. H. Linfield, and R. W. Kelsall, “Terahertz ambipolar dual-wavelength quantum cascade laser,” Opt. Express17(22), 19926–19932 (2009).
    [CrossRef] [PubMed]
  5. T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
    [CrossRef]
  6. R. Nelander and A. Wacker, “Temperature dependence of gain profile for terahertz quantum cascade lasers,” Appl. Phys. Lett.92(8), 081102 (2008).
    [CrossRef]
  7. C. Jirauschek and P. Lugli, “Monte-Carlo-based spectral gain analysis for terahertz quantum cascade lasers,” J. Appl. Phys.105(12), 123102 (2009).
    [CrossRef]
  8. A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
    [CrossRef]
  9. Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
    [CrossRef]
  10. M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
    [CrossRef]
  11. P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
    [CrossRef]
  12. S. Fathololoumi, E. Dupont, C. W. I. Chan, Z. R. Wasilewski, S. R. Laframboise, D. Ban, A. Mátyás, C. Jirauschek, Q. Hu, and H. C. Liu, “Terahertz quantum cascade lasers operating up to ∼ 200 K with optimized oscillator strength and improved injection tunneling,” Opt. Express20(4), 3866–3876 (2012).
    [CrossRef] [PubMed]
  13. T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
    [CrossRef]
  14. H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
    [CrossRef]
  15. C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
    [CrossRef]
  16. M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
    [CrossRef]
  17. R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
    [CrossRef] [PubMed]
  18. T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
    [CrossRef]
  19. T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
    [CrossRef]
  20. H. Detz, A. M. Andrews, M. Nobile, P. Klang, E. Mujagić, G. Hesser, W. Schrenk, F. Schäffler, and G. Strasser, “Intersubband optoelectronics in the InGaAs/GaAsSb material system,” J. Vac. Sci. Technol. B. 28, C3G19 (2010).
    [CrossRef]
  21. J. Faist, F. Capasso, C. Sirtori, D. L. Sivco, and A. Y. Cho, “Intersubband Transitions in Quantum Wells: Physics and Device Applications II, Semiconductor,” Semiconductor and Semimetals Vol. 66 (Academic Press, San Diego, 2000).
  22. C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
    [CrossRef]
  23. M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
    [CrossRef]

2012 (4)

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

S. Fathololoumi, E. Dupont, C. W. I. Chan, Z. R. Wasilewski, S. R. Laframboise, D. Ban, A. Mátyás, C. Jirauschek, Q. Hu, and H. C. Liu, “Terahertz quantum cascade lasers operating up to ∼ 200 K with optimized oscillator strength and improved injection tunneling,” Opt. Express20(4), 3866–3876 (2012).
[CrossRef] [PubMed]

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

2011 (1)

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

2010 (5)

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

F. Capasso, “High-performance midinfrared quantum cascade lasers,” Opt. Eng.49(11), 111102 (2010).
[CrossRef]

2009 (4)

L. Lever, N. M. Hinchcliffe, S. P. Khanna, P. Dean, Z. Ikonic, C. A. Evans, A. G. Davies, P. Harrison, E. H. Linfield, and R. W. Kelsall, “Terahertz ambipolar dual-wavelength quantum cascade laser,” Opt. Express17(22), 19926–19932 (2009).
[CrossRef] [PubMed]

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

C. Jirauschek and P. Lugli, “Monte-Carlo-based spectral gain analysis for terahertz quantum cascade lasers,” J. Appl. Phys.105(12), 123102 (2009).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

2008 (1)

R. Nelander and A. Wacker, “Temperature dependence of gain profile for terahertz quantum cascade lasers,” Appl. Phys. Lett.92(8), 081102 (2008).
[CrossRef]

2007 (2)

B. Williams, “Terahertz quantum-cascade lasers,” Nat. Photonics1(9), 517–525 (2007).
[CrossRef]

H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
[CrossRef]

2001 (1)

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

1999 (1)

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

1994 (1)

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

1982 (1)

T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
[CrossRef]

Aers, G. C.

H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
[CrossRef]

Akiyama, H.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Ando, T.

T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
[CrossRef]

Andrews, A. M.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Aung, N. L.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

Baba, M.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Ban, D.

Beck, M.

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

Benz, A.

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Bhatt, A. M.

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

Bismuto, A.

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

Brandstetter, M.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

Cao, J. C.

H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
[CrossRef]

Capasso, F.

F. Capasso, “High-performance midinfrared quantum cascade lasers,” Opt. Eng.49(11), 111102 (2010).
[CrossRef]

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Chan, C. W. I.

Chashnikova, M.

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

Chiu, Y.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

Cho, A. Y.

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Collins, D. A.

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Davies, A. G.

Dean, P.

Detz, H.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Deutsch, C.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Dikmelik, Y.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Dupont, E.

Escarra, M. D.

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

Evans, C. A.

Faist, J.

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

Fan, J. Y.

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

Fan, J.-Y.

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Fasching, G.

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Fathololoumi, S.

Feenstra, R. M.

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Flores, Y.

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

Fowler, A. B.

T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
[CrossRef]

Franz, K. J.

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Gmachl, C.

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Gmachl, C. F.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Harrison, P.

Hinchcliffe, N. M.

Hoffman, A. J.

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

Hu, Q.

Hutchinson, A. L.

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Ikonic, Z.

Jirauschek, C.

Kelsall, R. W.

Khanna, S. P.

Khurgin, J. B.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Klang, P.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Klimeck, G.

T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
[CrossRef]

Krall, M.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

Kubis, T.

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
[CrossRef]

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Laframboise, S. R.

Lever, L.

Linfield, E. H.

Liu, H. C.

Liu, P. Q.

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Lugli, P.

C. Jirauschek and P. Lugli, “Monte-Carlo-based spectral gain analysis for terahertz quantum cascade lasers,” J. Appl. Phys.105(12), 123102 (2009).
[CrossRef]

Luo, H.

H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
[CrossRef]

Masselink, W. T.

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

Mátyás, A.

McGill, T. C.

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Mehrotra, S. R.

T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
[CrossRef]

Monastyrskyi, G.

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

Mujagic, E.

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Nelander, R.

R. Nelander and A. Wacker, “Temperature dependence of gain profile for terahertz quantum cascade lasers,” Appl. Phys. Lett.92(8), 081102 (2008).
[CrossRef]

Nobile, M.

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Noda, T.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Sakaki, H.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Schrenk, W.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Semtsiv, M. P.

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

Sivco, D. L.

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Stern, F.

T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
[CrossRef]

Strasser, G.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

Takahashi, T.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Terazzi, R.

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

Ting, D. Z.-Y.

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Tredicucci, A.

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Unterrainer, K.

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

Unuma, T.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Vogl, P.

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Wacker, A.

R. Nelander and A. Wacker, “Temperature dependence of gain profile for terahertz quantum cascade lasers,” Appl. Phys. Lett.92(8), 081102 (2008).
[CrossRef]

Wang, M. W.

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Wang, X.

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

Wasilewski, Z. R.

Williams, B.

B. Williams, “Terahertz quantum-cascade lasers,” Nat. Photonics1(9), 517–525 (2007).
[CrossRef]

Yeh, C.

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Yoshita, M.

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

Appl. Phys. Lett. (10)

A. Bismuto, R. Terazzi, M. Beck, and J. Faist, “Influence of the growth temperature on the performance of strain-balanced quantum cascade lasers,” Appl. Phys. Lett.98(9), 091105 (2011).
[CrossRef]

Y. Chiu, Y. Dikmelik, P. Q. Liu, N. L. Aung, J. B. Khurgin, and C. F. Gmachl, “Importance of interface roughness induced intersubband scattering in mid-infrared quantum cascade lasers,” Appl. Phys. Lett.101(17), 171117 (2012).
[CrossRef]

M. P. Semtsiv, Y. Flores, M. Chashnikova, G. Monastyrskyi, and W. T. Masselink, “Low-threshold intersubband laser based on interface-scattering-rate engineering,” Appl. Phys. Lett.100(16), 163502 (2012).
[CrossRef]

T. Kubis, S. R. Mehrotra, and G. Klimeck, “Design concepts for terahertz quantum cascade lasers:Proposal for terahertz laser efficiency improvements,” Appl. Phys. Lett.97(26), 261106 (2010).
[CrossRef]

H. Luo, S. R. Laframboise, Z. R. Wasilewski, G. C. Aers, H. C. Liu, and J. C. Cao, “Terahertz quantum-cascade lasers based on a three-well active module,” Appl. Phys. Lett.90(4), 041112 (2007).
[CrossRef]

C. Deutsch, A. Benz, H. Detz, P. Klang, M. Nobile, A. M. Andrews, W. Schrenk, T. Kubis, P. Vogl, G. Strasser, and K. Unterrainer, “Terahertz quantum cascade lasers based on type II InGaAs/GaAsSb/InP,” Appl. Phys. Lett.97(26), 261110 (2010).
[CrossRef]

M. Nobile, H. Detz, E. Mujagić, A. M. Andrews, P. Klang, W. Schrenk, and G. Strasser, “Midinfrared intersubband absorption in InGaAs/GaAsSb multiple quantum wells,” Appl. Phys. Lett.95(4), 041102 (2009).
[CrossRef]

T. Unuma, T. Takahashi, T. Noda, M. Yoshita, H. Sakaki, M. Baba, and H. Akiyama, “Effects of interface roughness and phonon scattering on intersubband absorption linewidth in a GaAs quantum well,” Appl. Phys. Lett.78(22), 3448 (2001).
[CrossRef]

R. Nelander and A. Wacker, “Temperature dependence of gain profile for terahertz quantum cascade lasers,” Appl. Phys. Lett.92(8), 081102 (2008).
[CrossRef]

C. Deutsch, M. Krall, M. Brandstetter, H. Detz, A. M. Andrews, P. Klang, W. Schrenk, G. Strasser, and K. Unterrainer, “High performance InGaAs/GaAsSb terahertz quantum cascade lasers operating up to 142 K,” Appl. Phys. Lett.101(21), 211117 (2012).
[CrossRef]

IEEE Photon. J. (1)

M. D. Escarra, A. Benz, A. M. Bhatt, A. J. Hoffman, X. Wang, J. Y. Fan, and C. Gmachl, “Thermoelectric effect in quantum cascade lasers,” IEEE Photon. J.2(3), 500–509 (2010).
[CrossRef]

J. Appl. Phys. (1)

C. Jirauschek and P. Lugli, “Monte-Carlo-based spectral gain analysis for terahertz quantum cascade lasers,” J. Appl. Phys.105(12), 123102 (2009).
[CrossRef]

Nat. Photonics (2)

P. Q. Liu, A. J. Hoffman, M. D. Escarra, K. J. Franz, J. B. Khurgin, Y. Dikmelik, X. Wang, J.-Y. Fan, and C. F. Gmachl, “Highly power-efficient quantum cascade lasers,” Nat. Photonics4(2), 95–98 (2010).
[CrossRef]

B. Williams, “Terahertz quantum-cascade lasers,” Nat. Photonics1(9), 517–525 (2007).
[CrossRef]

Opt. Eng. (1)

F. Capasso, “High-performance midinfrared quantum cascade lasers,” Opt. Eng.49(11), 111102 (2010).
[CrossRef]

Opt. Express (2)

Phys. Rev. B (1)

T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, and C. Deutsch, “Theory of nonequilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers,” Phys. Rev. B79(19), 195323 (2009).
[CrossRef]

Phys. Rev. Lett. (1)

R. M. Feenstra, D. A. Collins, D. Z.-Y. Ting, M. W. Wang, and T. C. McGill, “Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy,” Phys. Rev. Lett.72(17), 2749–2752 (1994).
[CrossRef] [PubMed]

Rev. Mod. Phys. (1)

T. Ando, A. B. Fowler, and F. Stern, “Electronic properties of two-dimensional systems,” Rev. Mod. Phys.54(2), 437–672 (1982).
[CrossRef]

Science (1)

C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, F. Capasso, and A. Y. Cho, “Bidirectional semiconductor laser,” Science286(5440), 749–752 (1999).
[CrossRef] [PubMed]

Other (2)

H. Detz, A. M. Andrews, M. Nobile, P. Klang, E. Mujagić, G. Hesser, W. Schrenk, F. Schäffler, and G. Strasser, “Intersubband optoelectronics in the InGaAs/GaAsSb material system,” J. Vac. Sci. Technol. B. 28, C3G19 (2010).
[CrossRef]

J. Faist, F. Capasso, C. Sirtori, D. L. Sivco, and A. Y. Cho, “Intersubband Transitions in Quantum Wells: Physics and Device Applications II, Semiconductor,” Semiconductor and Semimetals Vol. 66 (Academic Press, San Diego, 2000).

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Figures (3)

Fig. 1
Fig. 1

Nominally symmetric active region of a terahertz quantum cascade laser biased with either bias polarity. The symmetry is broken by the different quality of the normal and inverted interfaces with respect to the growth direction. The inverted interfaces are sketched as a rough line in the band structure. (a) Positive top bias polarity results in an electron flow incident on the inverted interfaces. (b) The cross-sectional TEM picture confirms the interface asymmetry in the InGaAs/GaAsSb material system and the enhanced roughness of inverted interface. (c) Negative polarity reverses the current flow and electrons are moving against the normal interfaces. The influence of interface roughness scattering can therefore be studied by simply switching between the bias polarities.

Fig. 2
Fig. 2

Comparison of the different active region designs and light-current-voltage characteristics of each sample measured with both operating polarities. (a) The layer sequence of sample 1 is 3.0/14.0/1.0/14.0/3.0/2.0/22.0/2.0 nm. For sample 2 the layer sequence is modified to 3.0/13.3/1.0/13.3/3.0/2.0/18.8/2.0 nm, which results in a better depletion of the lower laser level due to optimized subband alignment and energy separation (E21). Sample 3 employs thinner injection/extraction barriers for stronger tunneling coupling. The layer sequence is 2.8/13.0/0.9/13.0/2.8/1.9/20.5/1.9 nm. GaAsSb barriers are in bold fonts. The Si doping density is 1 × 1016 cm−3 in the underlined sections. (b) Sample 1 only shows lasing for negative polarity. (c) Sample 2 works with both bias polarities but exhibits a significant transport and performance difference. (d) Thinner barriers in sample 3 enhance the tunneling coupling and reduce the threshold difference.

Fig. 3
Fig. 3

Normalized spectra of sample 2 recorded in both bias polarities at the maximum optical output power and at 5 K. The main lasing modes are observed in both spectra. It indicates that the spectral position of the gain is not influenced by the applied polarity and the resulting subband level alignment/spacing is identical.

Tables (1)

Tables Icon

Table 1 Performance comparison of three different symmetric InGaAs/GaAsSb active regions and their polarity-dependent asymmetry

Equations (1)

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τ if 1 = π m * 3 δ U 2 ( Λ 1 2 Δ 2 1 e Λ 1 2 q 2 if 4 norm ψ 2 i ( z norm ) ψ 2 f ( z norm )+ Λ 2 2 Δ 2 2 e Λ 2 2 q 2 if 4 inv ψ 2 i ( z inv ) ψ 2 f ( z inv ) ).

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