Post-Matrix Product State Methods: To tangent space and beyond

Jutho Haegeman; Tobias J. Osborne; Frank Verstraete

doi:10.1103/physrevb.88.075133

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arXiv · 1305.1894

Post-Matrix Product State Methods: To tangent space and beyond

Jutho Haegeman·Tobias J. Osborne·Frank Verstraete

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Abstract

We develop in full detail the formalism of tangent states to the manifold of matrix product states, and show how they naturally appear in studying time-evolution, excitations and spectral functions. We focus on the case of systems with translation invariance in the thermodynamic limit, where momentum is a well defined quantum number. We present some new illustrative results and discuss analogous constructions for other variational classes. We also discuss generalizations and extensions beyond the tangent space, and give a general outlook towards post matrix product methods.

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Jutho Haegeman, Tobias J. Osborne, Frank Verstraete. 2013-05-08. Post-Matrix Product State Methods: To tangent space and beyond. https://doi.org/10.1103/physrevb.88.075133

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