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arXiv · 1304.0316

Low Rank Approximation Method for Efficient Green's Function Calculation of Dissipative Quantum Transport

Lang Zeng·Yu He·Michael Povolotsky·XiaoYan Liu·Gerhard Klimeck·Tillmann Kubis
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Abstract

In this work, the low rank approximation concept is extended to the non-equilibrium Green's function (NEGF) method to achieve a very efficient approximated algorithm for coherent and incoherent electron transport. This new method is applied to inelastic transport in various semiconductor nanodevices. Detailed benchmarks with exact NEGF solutions show 1) a very good agreement between approximated and exact NEGF results, 2) a significant reduction of the required memory, and 3) a large reduction of the computational time (a factor of speed up as high as 150 times is observed). A non-recursive solution of the inelastic NEGF transport equations of a 1000 nm long resistor on standard hardware illustrates nicely the capability of this new method.

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Lang Zeng, Yu He, Michael Povolotsky, XiaoYan Liu, Gerhard Klimeck, Tillmann Kubis. 2013-04-01. Low Rank Approximation Method for Efficient Green's Function Calculation of Dissipative Quantum Transport. https://doi.org/10.1063/1.4809638

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