Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Wide applicability of high $T_c$ pairing originating from coexisting
  wide and incipient narrow bands in quasi one dimension   We study superconductivity in the Hubbard model on various
quasi-one-dimensional lattices with coexisting wide and narrow bands
originating from multiple sites within a unit cell, where each site corresponds
to a single orbital. The systems studied are the 2-leg and 3-leg ladders, the
diamond chain, and the criss-cross ladder. These one-dimensional lattices are
weakly coupled to form two-dimensional (quasi-one-dimensional) ones, and the
fluctuation exchange approximation is adopted to study
spin-fluctuation-mediated superconductivity. When one of the bands is perfectly
flat, and the Fermi level, intersecting the wide band, is placed in the
vicinity of the flat band, superconductivity arising from the interband
scattering processes is found to be strongly enhanced owing to the combination
of the light electron mass of the wide band and the strong pairing interaction
due to the large density of states of the flat band. Even when the narrow band
has finite band width, the pairing mechanism still works since the edge of the
narrow band, due to its large density of states, plays the role of the flat
band. The results indicate the generality of the high $T_c$ pairing mechanism
due to coexisting wide and "incipient" narrow bands in quasi-one-dimensional
systems.

22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th