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.
Terahertz quantum cascade lasers
TREDICUCCI, ALESSANDRO
Primo
;
2004-01-01
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
