Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theoretical Limits of Photovoltaics Efficiency and Possible Improvements
  by Intuitive Approaches Learned from Photosynthesis and Quantum Coherence   In this review, we present and discussed the main trends in photovoltaics
with emphasize on the conversion efficiency limits. The theoretical limits of
various photovoltaics device concepts are presented and analyzed using a
flexible detailed balance model where more discussion emphasize is toward the
losses. Also, few lessons from nature and other fields to improve the
conversion efficiency in photovoltaics are presented and discussed as well.
From photosynthesis, the perfect exciton transport in photosynthetic complexes
can be utilized for PVs. Also, we present some lessons learned from other
fields like recombination suppression by quantum coherence. For example, the
coupling in photosynthetic reaction centers is used to suppress recombination
in photocells.

2
The categories of this paper are: math
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
3
The categories of this paper are: physics