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In this work we investigate some steady-state stochastic properties of hot electron dynamics in bulk n-type GaAs in the presence of crossed, static electric and magnetic fields. To this aim, a single particle, three valleys-Monte Carlo method is adopted. In order to include the non-parabolicity of valleys a local parabolic approximation is performed allowing us to get an analytic expression for k(t) during free flights. It is shown how the room temperature-spectrum of longitudinal velocity fluctuations is markedly affected by the oscillations at the cyclotron frequency and is lowered or increased by the magnetic field depending on the considered frequency. On the contrary, the transverse spectral density turns out to be reduced in a suitable range of electric field strengths, as a consequence of the lowering of transverse velocity fluctuations’s variance. We found that in the same electric field range the mean kinetic energy is lowered too. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work we have investigated the noise properties of hot electrons in n-type GaAs in crossed electric and magnetic fields by single-particle Monte Carlo simulations. The motion of electrons during free flights is treated classically. Nonparabolicity of valleys is taken into account by means of a local parabolic approximation. The velocity auto-correlation function and its spectral density of fluctuations turn out to be strongly affected by the presence of the magnetic field. In particular, significant signatures of nonparabolicity and nonlinearity are observed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The nonlinear response of electrons in a GaAs bulk semiconductor placed in an oscillating electric field with frequency in the far infrared domain is studied using the Monte Carlo method. The drift velocity obtained from the Monte Carlo simulation is used to obtain the efficiency of high order harmonics generation. Harmonics up to the 15th order with an efficiency of 10[sup -7] are resolved for a field with amplitude of E=50 kV/cm. It is also reported the dependence of the first four odd harmonics efficiencies on the lattice temperature in the range 80–400 K and on the amplitude of the electric field in the range 5–100 kV/cm. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]