Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum simulation of discrete-time Hamiltonians using directionally
  unbiased linear optical multiports   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.

34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th