Studying quantum phasebased electronic devices
Abstract
This report summarizes work confined to use of the moments of the density matrix, for examining transport in quantum phase based devices. There are two significant features of the approach: (1) the introduction of Bohm's quantum potential, and (2) the use of moment equations which are selfconsistently coupled to Poisson's equation. There were a number of significant approximations made during this reporting period that are currently being eliminated: (1) Only two of the minimum of three moment equations have been implemented. (2) Boltsmann statistics was invoked. The results show for a double barrier structure with 500 Angstrom spacerlayers considerable structure in the charge distribution. At low values of bias and corresponding low values of current there is a buildup of charge upstream of the first barrier, as well as tunnelling into the well. At a critical value of bias a local instability of current occurs and the solutions shows a qualitative difference. Accumulation at the upstream barrier is only marginally altered, and there is a significant charge buildup in the well. The instability appears to be a precursor for this charge buildup.
 Publication:

Annual Report
 Pub Date:
 September 1988
 Bibcode:
 1988srai.reptR....G
 Keywords:

 Charge Distribution;
 Electron Tunneling;
 Poisson Equation;
 Quantum Electronics;
 Quantum Wells;
 Transport Theory;
 Bias;
 Boltzmann Distribution;
 Electric Charge;
 Quantum Theory;
 Stability;
 Electronics and Electrical Engineering