Unipolar semiconductor injection lasers emitting at THz frequencies (from 4.3 THz down to 2.8 THz) are discussed. The devices are based on interminiband transitions in chirped GaAs/AlGaAs superlattices that are arranged in a quantum-cascade scheme. The core, featuring about 100 repetitions of this type of superlattice, is embedded into a novel kind of waveguide loosely based on the surface plasmon concept, which allows low absorption losses and high confinement factors. These devices operate in pulsed mode up to a maximum temperature of 75 K (50 K in continuous wave) with several mW of output power and threshold current densities as low as 100 A/cm(2). A promising structure based on an interdigitated cascade is presented that allows operation above 90 K with high emitted powers. (C) 2003 Elsevier B.V. All rights reserved.
Autori interni: | TREDICUCCI, ALESSANDRO (Primo) | |
Autori: | Tredicucci, Alessandro; Kohler, R; Beltram, F; Beere, He; Linfield, Eh; Davies, Ag; Ritchie, Da | |
Titolo: | Terahertz quantum cascade lasers | |
Anno del prodotto: | 2004 | |
Abstract: | Unipolar semiconductor injection lasers emitting at THz frequencies (from 4.3 THz down to 2.8 THz) are discussed. The devices are based on interminiband transitions in chirped GaAs/AlGaAs superlattices that are arranged in a quantum-cascade scheme. The core, featuring about 100 repetitions of this type of superlattice, is embedded into a novel kind of waveguide loosely based on the surface plasmon concept, which allows low absorption losses and high confinement factors. These devices operate in pulsed mode up to a maximum temperature of 75 K (50 K in continuous wave) with several mW of output power and threshold current densities as low as 100 A/cm(2). A promising structure based on an interdigitated cascade is presented that allows operation above 90 K with high emitted powers. (C) 2003 Elsevier B.V. All rights reserved. | |
Digital Object Identifier (DOI): | 10.1016/j.physe.2003.11.137 | |
Appare nelle tipologie: | 1.1 Articolo in rivista |