An Approximate Framework for Quantum Transport Calculation with Model Order Reduction

TL;DR

This paper introduces a novel approximate computational framework combining a new X-formulation and model order reduction techniques to efficiently compute non-equilibrium charge densities in quantum transport simulations.

Contribution

It presents a new X-formulation for single-energy density calculation and a projection-based MOR approach to reduce computational complexity in NEGF-based quantum transport.

Findings

Numerical experiments confirm the efficiency of the new methods.

The framework reduces computational cost for large bias voltages.

The approach maintains accuracy while decreasing simulation time.

Abstract

A new approximate computational framework is proposed for computing the non-equilibrium charge density in the context of the non-equilibrium Green's function (NEGF) method for quantum mechanical transport problems. The framework consists of a new formulation, called the X-formulation, for single-energy density calculation based on the solution of sparse linear systems, and a projection-based nonlinear model order reduction (MOR) approach to address the large number of energy points required for large applied biases. The advantages of the new methods are confirmed by numerical experiments.