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[Licence| Download | New Version Template] aedj_v2_0.tar.gz(10324 Kbytes)
Manuscript Title: Implementation of the SU(2) Hamiltonian Symmetry for the DMRG Algorithm
Authors: G. Alvarez
Program title: DMRG++
Catalogue identifier: AEDJ_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 183(2012)2226
Programming language: C++.
Computer: PC.
Operating system: Multiplatform, tested on Linux.
Has the code been vectorised or parallelized?: Yes. 1 to 8 processors with MPI, 2 to 4 cores with pthreads.
RAM: 1GB (256MB is enough to run the included test)
Keywords: Density-matrix renormalization group, DMRG, Strongly correlated electrons, Generic programming.
PACS: 71.10.Fd 71.27.+a 78.67.Hc.
Classification: 23.

External routines: BLAS and LAPACK

Nature of problem:
Strongly correlated electrons systems, display a broad range of important phenomena, and their study is a major area of research in condensed matter physics. In this context, model Hamiltonians are used to simulate the relevant interactions of a given compound, and the relevant degrees of freedom. These studies rely on the use of tight-binding lattice models that consider electron localization, where states on one site can be labeled by spin and orbital degrees of freedom. The calculation of properties from these Hamiltonians is a computational intensive problem, since the Hilbert space over which these Hamiltonians act grows exponentially with the number of sites on the lattice.

Solution method:
The DMRG is a numerical variational technique to study quantum many body Hamiltonians. For one-dimensional and quasi one-dimensional systems, the DMRG is able to truncate, with bounded errors and in a general and efficient way, the underlying Hilbert space to a constant size, making the problem tractable.

Running time:
Varies. The test suite provided takes about 10 minutes to run on a serial machine.