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arXiv · 1310.4153

Hamiltonian quantum simulation with bounded-strength controls

Adam D. Bookatz·Pawel Wocjan·Lorenza Viola
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Abstract

We propose dynamical control schemes for Hamiltonian simulation in many-body quantum systems that avoid instantaneous control operations and rely solely on realistic bounded-strength control Hamiltonians. Each simulation protocol consists of periodic repetitions of a basic control block, constructed as a suitable modification of an "Eulerian decoupling cycle," that would otherwise implement a trivial (zero) target Hamiltonian. For an open quantum system coupled to an uncontrollable environment, our approach may be employed to engineer an effective evolution that simulates a target Hamiltonian on the system, while suppressing unwanted decoherence to the leading order. We present illustrative applications to both closed- and open-system simulation settings, with emphasis on simulation of non-local (two-body) Hamiltonians using only local (one-body) controls. In particular, we provide simulation schemes applicable to Heisenberg-coupled spin chains exposed to general linear decoherence, and show how to simulate Kitaev's honeycomb lattice Hamiltonian starting from Ising-coupled qubits, as potentially relevant to the dynamical generation of a topologically protected quantum memory. Additional implications for quantum information processing are discussed.

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Adam D. Bookatz, Pawel Wocjan, Lorenza Viola. 2013-10-15. Hamiltonian quantum simulation with bounded-strength controls. https://doi.org/10.1088/1367-2630/16/4/045021

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