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arXiv · 1604.01198

Towards Realistic Time-Resolved Simulations of Quantum Devices

Joseph Weston·Xavier Waintal
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Abstract

We report on our recent efforts to perform realistic simulations of large quantum devices in the time domain. In contrast to d.c. transport where the calculations are explicitly performed at the Fermi level, the presence of time-dependent terms in the Hamiltonian makes the system inelastic so that it is necessary to explicitly enforce the Pauli principle in the simulations. We illustrate our approach with calculations for a flying qubit interferometer, a nanoelectronic device that is currently under experimental investigation. Our calculations illustrate the fact that many degrees of freedom (16,700 tight-binding sites in the scattering region) and long simulation times (80,000 times the inverse Bandwidth of the tight-binding model) can be easily achieved on a local computer.

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Joseph Weston, Xavier Waintal. 2016-04-05. Towards Realistic Time-Resolved Simulations of Quantum Devices. https://doi.org/10.1007/s10825-016-0855-9

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