Quantum Noise in Nanotransistors

Abstract

The Landauer-Buttiker approach for simulation of nanometer-scale field-effect transistors is developed to incorporate a calculation of noise at arbitrary temperature and applied voltage. The method allows for both shot noise and Johnson–Nyquist (thermal) noise. The impact of random impurities in the channel and doping profile in source/drain contacts on current and noise was cleared up. The quantum noise is compared with that originating from a classical description of motion along the channel. Unlike the classical renormalized shot noise the quantum noise is smaller than the current. This discrepancy could be a crucial evidence for quantum transport in a transistor channel. From practical point of view that provides a possibility to reduce a shot noise in quantum nanotransistors.