Wide band-gap materials
Permanent staff: Francois Julien
Post-Doc: Arnaud Jollivet
Wide band gap materials such as GaN/AlGaN or ZnO/ ZnMgO offer many advantages for quantum cascade devices operating in a wide spectral range covering the near-infrared, mid-infrared and THz domains. In particular the large energy of LO-phonons (92 meV for GaN, 72 meV for ZnO) opens prospects for QCLs operating at record large temperatures.
Collaboration (CNRS-CRHEA, III-V Lab)
In the frame of two European projects, we have demonstrated the potential of GaN-based intersubband devices for optoelectronics devices operated at room temperature at telecom wavelengths, such as electro-optical modulators, ultrafast quantum cascade detectors or quantum well and quantum dot light emitters. The current activities focus on the development of quantum cascade lasers and detectors at THz frequencies (1-15 THz).
Ref: •Sakr S., Crozat P., Gacemi D., Kotsar Y., Pesach A., Quach P., Isac N., Tchernycheva M., Vivien L., Bahir G., Monroy E., Julien F. H., "GaN/AlGaN waveguide quantum cascade photodetectors at λ≈1.55 μm with enhanced responsivity and ∼40 GHz frequency bandwidth", Appl. Phys. Lett. 102, 011135 (2013) http://dx.doi.org/ 10.1063/1.4775374
•Sakr S., Giraud E., Tchernycheva M., Isac N., Quach P., Warde E., Grandjean N., Julien F. H., "A simplified GaN/ AlGaN quantum cascade detector with an alloy extractor", Appl. Phys. Lett. 101, 251101 (2012) http://dx.doi.org/ 10.1063/1.4772501
•H. Machhadani, M. Tchernycheva, S. Sakr, L. Rigutti, R. Colombelli, E. Warde, C. Mietze, D. J. As, F. H. Julien, «Intersubband absorption of cubic GaN/Al(Ga)N quantum wells in the near-infrared to terahertz spectral range», Phys. Rev. B 83, 075313 (2011) DOI: 10.1103/PhysRevB.83.075313
Project: Fet-OPEN UNITRIDE, ANR OptoTeraGaN
Collaboration (CNRS-CRHEA, ISOM-Madrid, TU-Wien, ETH-Zurich)
In the frame of the Fet-OPEN European project ZOTERAC, we are investigating the potential of ZnO-ZnMgO devices grown on m-plane for quantum cascade devices operated in the near-infrared to THz spectral range. We have performed photo-induced intersubband spectroscopy to assess basic material parameters such as the conduction band offset. The study has revealed a new phenomenon related to excitonic transitions induced by intersubband absorption. We have also developed the first quantum cascade detectors in this material system. Our current activities focus on the development of THz quantum cascade devices.
Ref: •N. Le Biavan, M. Hugues, M. Montes Bajo, J. Tamayo-Arriola, A. Jollivet, D. Lefebvre, Y. Cordier, B. Vinter, F.-H. Julien, A. Hierro, J.-M. Chauveau, “Homoepitaxy of non-polar ZnO/(Zn,Mg)O multi-quantum wells: from a precise growth control to the observation of intersubband transitions” , Appl. Phys. Lett. 111, 231903 (2017).
•A. Jollivet, B. Hinkov, S. Pirotta, H. Hoang, S. Derelle, J. Jaeck, M. Tchernycheva, R. Colombelli, A. Bousseksou, M. Hugues, N. Le Biavan, J. Tamayo-Arriola, M. Montes Bajo, L. Rigutti, A. Hierro, G. Strasser, J.-M. Chauveau, and F. H. Julien, “Short infrared wavelength quantum cascade detectors based on m-plane ZnO/ZnMgO quantum wells”, Appl. Phys. Lett. 113, 251104 (2018); doi: 10.1063/1.5058120
Project: Fet-OPEN ZOTERAC