Abstract-Magnetic-field assisted performance of InGaAs/GaAsSb terahertz quantum cascade lasers

Simon Maëro¹, Louis-Anne de Vaulchier¹, Yves Guldner¹,Christoph Deutsch², Michael Krall², Tobias Zederbauer³,Gottfried Strasser³, and Karl Unterrainer^{2
http://apl.aip.org/resource/1/applab/v103/i5/p051116_s1?isAuthorized=no&}

We report on a magnetic-field investigation of a In_0.53Ga_0.47As/GaAs_0.51Sb_0.49terahertz quantum cascade laser. Owing to the suppression of inter-Landau level non-radiative scattering, the device performances are strongly improved at high magnetic field. Working temperature up to 190 K and current threshold of 450 A/cm² are measured at 11 T, comparable to the state-of-the-art GaAs/AlGaAs terahertz lasers. The nominally symmetric three-well structure presents significantly better performance with negative bias polarisation because of the inverted-interface roughness impact on the laser action.

© 2013 AIP Publishing LLC

Direct surface cyclotron resonance terahertz emission from a quantum cascade structure

http://apl.aip.org/resource/1/applab/v100/i10/p102103_s1?isAuthorized=no

François-Régis Jasnot¹, Louis-Anne de Vaulchier¹, Yves Guldner¹, Gérald Bastard¹, Angela Vasanelli², Christophe Manquest², Carlo Sirtori², Mattias Beck³, and Jérôme Faist³

¹Laboratoire Pierre Aigrain, Ecole Normale Supérieure, CNRS (UMR 8551), 24 rue Lhomond, 75231 Paris Cedex 05, France 
²Laboratoire Matériaux et Phénoménes Quantiques, Université Paris Diderot—Paris 7, CNRS—UMR 7162, Bâtiment Condorcet, 75205 Paris Cedex 13, France 

³Institute of Quantum Electronics, ETH Zürich, CH-8093 Zürich, Switzerland 

A strong magnetic field applied along the growth direction of a semiconductor quantum well gives rise to a spectrum of discrete energy states, the Landau levels. By combining quantum engineering of a quantum cascade structure with a static magnetic field, we can selectively inject electrons into the excited Landau level of a quantum well and realize a tunable surface emitting device based on cyclotron emission. By applying the appropriate magnetic field between 0 and 12 T, we demonstrate emission from a single device over a wide range of frequencies (1-2 THz and 3-5 THz).

© 2012 American Institute of Physics