Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nanohelices as superlattices: Bloch oscillations and electric dipole
  transitions   Subjecting a nanohelix to a transverse electric field gives rise to
superlattice behavior with tunable electronic properties. We theoretically
investigate such a system and find Bloch oscillations and negative differential
conductance when a longitudinal electric field (along the nanohelix axis) is
also applied. Furthermore, we study dipole transitions across the
transverse-electric-field-induced energy gap, which can be tuned to the
eulogized terahertz frequency range by experimentally attainable external
fields. We also reveal a photogalvanic effect by shining circularly polarized
light onto our helical quantum wire.

35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin