Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Root-N Krylov-space correction-vectors for spectral functions with the
  density matrix renormalization group   We propose a method to compute spectral functions of generic Hamiltonians
using the density matrix renormalization group (DMRG) algorithm directly in the
frequency domain, based on a modified Krylov space decomposition to compute the
correction-vectors. Our approach entails the calculation of the root-N (N=2 is
the standard square root) of the Hamiltonian propagator using Krylov space
decomposition, and repeating this procedure N times to obtain the actual
correction-vector. We show that our method greatly alleviates the burden of
keeping a large bond dimension at large target frequencies, a problem found
with conventional correction-vector DMRG, while achieving better computational
performance at large N. We apply our method to spin and charge spectral
functions of t-J and Hubbard models in the challenging two-leg ladder geometry,
and provide evidence that the root-N approach reaches a much improved
resolution compared to conventional correction-vector.

14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex