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arXiv · 1103.0936

Time-dependent variational principle for quantum lattices

Jutho Haegeman·J. Ignacio Cirac·Tobias J. Osborne·Iztok Pizorn·Henri Verschelde·Frank Verstraete
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Abstract

We develop a new algorithm based on the time-dependent variational principle applied to matrix product states to efficiently simulate the real- and imaginary time dynamics for infinite one-dimensional quantum lattice systems. This procedure: (1) is argued to be optimal; (2) does not rely on the Trotter decomposition and thus has no Trotter error; (3) explicitly preserves all symmetries and conservation laws; and (4) has low computational complexity. The algorithm is illustrated using both imaginary time and real-time examples.

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Jutho Haegeman, J. Ignacio Cirac, Tobias J. Osborne, Iztok Pizorn, Henri Verschelde, Frank Verstraete. 2011-05-26. Time-dependent variational principle for quantum lattices. https://doi.org/10.1103/physrevlett.107.070601

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