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arXiv · 1508.00570

Rapid adiabatic preparation of injective PEPS and Gibbs states

Yimin Ge·András Molnár·J. Ignacio Cirac
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Abstract

We propose a quantum algorithm for many-body state preparation. It is especially suited for injective PEPS and thermal states of local commuting Hamiltonians on a lattice. We show that for a uniform gap and sufficiently smooth paths, an adiabatic runtime and circuit depth of $O(\operatorname{polylog}N)$ can be achieved for $O(N)$ spins. This is an almost exponential improvement over previous bounds. The total number of elementary gates scales as $O(N\operatorname{polylog}N)$. This is also faster than the best known upper bound of $O(N^2)$ on the mixing times of Monte Carlo Markov chain algorithms for sampling classical systems in thermal equilibrium.

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Yimin Ge, András Molnár, J. Ignacio Cirac. 2016-03-07. Rapid adiabatic preparation of injective PEPS and Gibbs states. https://doi.org/10.1103/physrevlett.116.080503

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