Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Influence of crystal structure on charge carrier effective masses in
  BiFeO$_3$   Ferroelectric-based photovoltaics have shown great promise as a source of
renewable energy, thanks to their in-built charge separation capability, yet
their efficiency is often limited by low charge carrier mobilities. In this
work, we compare the photovoltaic prospects of various phases of the
multiferroic material BiFeO$_3$ by evaluating their charge carrier effective
masses using first-principles simulations. We identify a tetragonal phase with
the promising combination of a large spontaneous polarisation and relatively
light charge carriers. From a systematic study of the octahedral distortions
present in BiFeO$_3$, we explain the relationship between structure and
effective masses in terms of the changes to the orbital character and overlap
at the band edges that result from changes in the geometry. The findings in
this study provide some design principles to engineer desired effective masses
in BiFeO$_3$ and similar materials through manipulation of their crystal
structures in experimentally accessible ways.

14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn