Coupling 3-D Maxwell's and Boltzmann's equations for analyzing a terahertz photoconductive switch

Optimization of THz pulses emitted by an InGaAs photoconductive switch

“…To simulate this PCS, we use an upgraded version of the modeling code described in [1][2]. This code solves the Maxwell's equations coupled with drift-diffusion equations using the three-dimensional finite different time domain (FDTD) method.…”

“…This code solves the Maxwell's equations coupled with drift-diffusion equations using the three-dimensional finite different time domain (FDTD) method. The structure is meshed with a non uniform grid because of the different space and time steps required by both the CPW structure and the transport of carriers in the small photo-conducting region [2].…”

“…The code is faster and numerically more stable thanks to the enhancement of the numerical procedures, from optimized formulations of material discontinuities and to from full transport calculation in all the structure including the highly doped contact areas whereas a fixed conductivity was forced before [2]. This code can run with simulation times longer than 12 ps without any divergence, thus allowing the observation of the total fall of the THz electric pulse.…”

The time-varying electric current in a Terahertz photoconductive switch

“…Coherent terahertz (THz) frequency radiation is emitted from the dc field biased semiconductor switch after excitation by an ultrafast laser pulse [2]. Because of the widespread application of THz electromagnetic waves [3], the mechanism by which THz radiation is generated when photoconductive switches are illuminated with subpicosecond laser pulses is an issue of debate [4]. Originally, the THz radiation was assumed to result from the acceleration of photoexcited carriers in the electric field in the surface of the switch.…”

2D time-domain electromagnetic macroscopic numerical modelling on parallel computer: application to the mm-wave silicon DIMPATT diode

“…The code has been developed in order to be run on a parallel computer by means of the domain decomposition method. Despite numerous EM/transport physical models have been already proposed [4][5][6], few results have been published on the EM physical modelling of active non linear distributed microwave semiconductor devices. Consequently, we have chosen the travelling-wave or Distributed IMPact Avalanche and Transit Time diode (DIMPATT) in order to validate our model.…”