Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum ratchet in disordered quantum walk   Symmetrically evolving discrete quantum walk results in dynamic localization
with zero mean displacement when the standard evolution operations are replaced
by a temporal disorder evolution operation. In this work we show that the
quantum ratchet action, that is, a directed transport in standard or disordered
discrete-time quantum walk can be realized by introducing a pawl like effect
realized by using a fixed coin operation at marked positions that is, different
from the ones used for evolution at other positions. We also show that the
combination of standard and disordered evolution operations can be optimized to
get the mean displacement of order $\propto$ t (number of walk steps). This
model of quantum ratchet in quantum walk is defined using only a set of
entangling unitary operators resulting in the coherent quantum transport.

32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat