In this paper we investigate, both theoretically and experimentally, nonequilibrium electron and phonon effects in quantum-cascade devices. In particular, we have developed a Monte Carlo-based global kinetic approach describing the complete interacting electronic subsystem (i.e., the full set of active-region and injector subbands) coupled to out-of-equilibrium longitudinal polar-optical (LO) phonons, which in turn will decay anharmonically into thermalized acoustic modes. Simulated results obtained for a prototypical terahertz emitting device show a very good agreement with measured data, evidencing how the nonequilibrium LO phonon population affects the electro-optical device performances. The latter may be qualitatively reproduced in terms of a global effective temperature of the heated phononic system. (C) 2010 American Institute of Physics. [doi:10.1063/1.3464977]
Impact of nonequilibrium phonons on the electron dynamics in terahertz quantum cascade lasers
TREDICUCCI, ALESSANDRO
2010
Abstract
In this paper we investigate, both theoretically and experimentally, nonequilibrium electron and phonon effects in quantum-cascade devices. In particular, we have developed a Monte Carlo-based global kinetic approach describing the complete interacting electronic subsystem (i.e., the full set of active-region and injector subbands) coupled to out-of-equilibrium longitudinal polar-optical (LO) phonons, which in turn will decay anharmonically into thermalized acoustic modes. Simulated results obtained for a prototypical terahertz emitting device show a very good agreement with measured data, evidencing how the nonequilibrium LO phonon population affects the electro-optical device performances. The latter may be qualitatively reproduced in terms of a global effective temperature of the heated phononic system. (C) 2010 American Institute of Physics. [doi:10.1063/1.3464977]I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
