Viewpoint: A little entanglement helps

Ulrich Schollwöck

Published May 11, 2009• 0 citations

Abstract

A new algorithm allows for the extremely efficient calculation of thermally averaged quantities in one dimension, in conjunction with the density matrix renormalization group method. The key is the judicious selection of a few representative states.

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Viewpoint: A little entanglement helps

Ulrich Schollwöck

Published May 11, 2009• 0 citations

OpenAlex

Abstract

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S=\frac{1}{2}

bound states in Heisenberg

S=1

junctions with two geometries, one where the junction consists of a single site, and the other where it consists of a triangle of three sites.

{\mathrm{CH}}_{2},

{\mathrm{H}}_{2}\mathrm{O},

and

{\mathrm{F}}_{2}

as well as the first excited state of

{\mathrm{CH}}_{2}.

Our largest calculations were carried out with 57 orbitals, the largest number of block states was 1500--2000, and the largest dimensions of the Hilbert space of the superblock configuration was 800 000--1 200 000.