Quantum simulation of discrete-time Hamiltonians using directionally unbiased linear optical multiports
Abstract
Recently, a generalization of the standard optical multiport was proposed [Phys. Rev. A 93, 043845 (2016)]. These directionally unbiased multiports allow photons to reverse direction and exit backwards from the input port, providing a realistic linear optical scattering vertex for quantum walks on arbitrary graph structures. Here, it is shown that arrays of these multiports allow the simulation of a range of discrete-time Hamiltonian systems. Examples are described, including a case where both spatial and internal degrees of freedom are simulated. Because input ports also double as output ports, there is substantial savings of resources compared to feed-forward networks carrying out the same functions. The simulation is implemented in a scalable manner using only linear optics, and can be generalized to higher dimensional systems in a straightforward fashion, thus offering a concrete experimentally achievable implementation of graphical models of discrete-time quantum systems.
Cite
@article{arxiv.1704.03108,
title = {Quantum simulation of discrete-time Hamiltonians using directionally unbiased linear optical multiports},
author = {David S. Simon and Casey A. Fitzpatrick and Shuto Osawa and Alexander V. Sergienko},
journal= {arXiv preprint arXiv:1704.03108},
year = {2017}
}