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arXiv · 1512.03318

Density matrix renormalization group on a cylinder in mixed real and momentum space

Johannes Motruk·Michael P. Zaletel·Roger S. K. Mong·Frank Pollmann
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Abstract

We develop a variant of the density matrix renormalization group (DMRG) algorithm for two-dimensional cylinders that uses a real space representation along the cylinder and a momentum space representation in the perpendicular direction. The mixed representation allows us to use the momentum around the circumference as a conserved quantity in the DMRG algorithm. Compared with the traditional purely real-space approach, we find a significant speedup in computation time and a considerable reduction in memory usage. Applying the method to the interacting fermionic Hofstadter model, we demonstrate a reduction in computation time by over 20-fold, in addition to a sixfold memory reduction.

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Johannes Motruk, Michael P. Zaletel, Roger S. K. Mong, Frank Pollmann. 2015-12-10. Density matrix renormalization group on a cylinder in mixed real and momentum space. https://doi.org/10.1103/physrevb.93.155139

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