Shot noise in resonant-tunneling structures

Abstract

We propose a quantum mechanical approach to noise in resonant tunneling structures, that can be applied in the whole range of transport regimes, from completely coherent to completely incoherent. In both limiting cases, well known results which have appeared in the literature are recovered. Shot noise reduction due to both Pauli exclusion and Coulomb repulsion, and their combined effect, are studied as a function of the rate of incoherent processes in the well (which are taken into account by means of a phenomenological relaxation time), and of temperature. Our approach allows the study of noise in a variety of operating conditions (i.e., equilibrium, sub-peak voltages, second resonance voltages), and as a function of temperature, explaining experimental results and predicting interesting new results, such as the dependence of noise on filled emitter states and the prediction of both increasing and decreasing shot noise with increasing temperature, depending on the structure. It also allows the determination of the major contributions to shot noise suppression by performing noise measurements at the second resonance voltage.

Shot noise in coupled dots and the “fractional charges”

“…(11) predicts a maximum suppression of one half of the Poissonian noise (for Γ L = Γ R ), in agreement with the known results [11] for independent particle models.…”

Self-consistent simulation of quantum shot noise in nanoscale electron devices

“…2 are in good agreement with the experimental results obtained by several different groups, with different resonant heterostructures. [12][13][14] Let us mention that scattering (apart from the electron-electron interaction) is not considered here and it can modify present results. In principle, our approach can accurately deal with additional scattering mechanisms by introducing their interaction/potential directly into the Hamiltonian [Eq.…”

“…Now, let us emphasize the capabilities of our proposal for dealing with the Poisson equation in a QM framework by providing a numerical example. We study the current through a resonant tunneling diode (RTD) which is a quantum-based device that has been exhaustively investigated, both, from theoretical 8,12,13 and experimental 12-14 points of view. We assume a standard GaAs/ AlAs heterostructure system with m = 0.067 m o (m o being the free electron mass).…”

Shot noise in mesoscopic conductors

“…absence of inelastic scattering), and concluded that inelastic processes do not affect shot noise suppression in quantum wells. Later, Iannaccone, Macucci, and Pellegrini [228] solved the master equation allowing explicitly for arbitrary inelastic scattering, and found that the noise suppression factor is given by Eq. (78) at zero temperature for arbitrary inelastic scattering provided the reservoirs are ideal.…”