Effect of inelastic scattering on resonant tunnelling in double-barrier heterostructures

Abstract

The effect of inelastic scattering on resonant tunnelling through a double-barrier semiconductor heterostructure is studied using the transfer matrix method incorporating a phenomenological damping of the wavefunction propagation in the quantum well. The coherent and sequential contributions to the transmission coefficient are evaluated analytically in a Lorentzian lineshape approximation close to resonance. In contrast to previous results it is found that the integrated total transmission coefficient is in general dependent on the inelastic scattering rate. Numerical calculations show that realistic values of current peak to valley ratios at 77 K are obtained assuming a mean inelastic scattering time approximately 10-12 s. The tunnelling is then almost totally sequential.