Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-polaron band structure and hole pockets in underdoped cuprates   We present a variational approach based on the string picture to analyze the
internal structure and dispersion of spin polarons with different symmetries in
an antiferromagnet. We then use this to discuss the properties of underdoped
cuprate superconductor within the `doped insulator' picture. The theory
explains the remnant Fermi surface for the undoped compunds, as well as hole
pockets, Fermi arcs, high energy pseudogap and the the mid-infrared band in
doped materials. Destructive interference between the phases of a photohole
near $\Gamma$ and the internal phases of the Zhang Rice singlet combined with
our theory moreover explains the `waterfall' phenomenon.

28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin