SHOT-NOISE IN DOUBLE-BARRIER QUANTUM STRUCTURES

Shot noise is calculated in a Double Barrier Resonant Tunneling Structure (DBRTS) by taking the space charge accumulated inside the quantum well into account. The calculation is self-consistent in nature and is obtained by simultaneously solving the Schrodinger and Poisson's equations. The calculation shows the suppression of shot noise in the positive differential resistance (PDR) region and an enhancement in the negative differential resistance region (NDR) of the DBRTS. This behavior is explained in terms of the auto- and cross-power density spectrum of current in the presence of space charge in the quantum well. Calculated shot noise factor shows a suppression in the PDR region(gamma = 0.31) and an enhancement in the NDR region (gamma = 9) as observed experimentally.