title: Broadband THz lasing from a photon-phonon quantum cascade structure.
abstract: Laser emission over a broad range of frequencies from 2.8 to 4.1 THz is reported for a two-quantum well, photon-phonon cascade structure. Maximum operating temperatures of 125 K are reported, with optical peak powers in eccess of 30 mW from a double-metal ridge waveguide. The broadband nature of the gain curve is identified as due to coherent coupling of the injector and upper lasing states. Internal quantum efficiencies reaching 43 % are evaluated at 10 K.The laser operates in both polarities, showing laser action in reverse bias up to a temperature of 90 K. Simulations based on a full treatment of the structure with density matrix formalism are also presented and discussed.
authors.affiliation: Institute of Quantum Electronics, Physics Department, ETH Zurich, Zurich, Switzerland. scalari@phys.ethz.ch
authors.forename: G
authors.initials: G
authors.lastname: Scalari
authors.forename: M I
authors.initials: MI
authors.lastname: Amanti
authors.forename: C
authors.initials: C
authors.lastname: Walther
authors.forename: R
authors.initials: R
authors.lastname: Terazzi
authors.forename: M
authors.initials: M
authors.lastname: Beck
authors.forename: J
authors.initials: J
authors.lastname: Faist