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arXiv · 1602.00926

Non-Markovian Dynamics in Chiral Quantum Networks with Spins and Photons

Tomás Ramos·Benoît Vermersch·Philipp Hauke·Hannes Pichler·Peter Zoller
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Abstract

We study the dynamics of chiral quantum networks consisting of nodes coupled by unidirectional or asymmetric bidirectional quantum channels. In contrast to familiar photonic networks where driven two-level atoms exchange photons via 1D photonic nanostructures, we propose and study a setup where interactions between the atoms are mediated by spin excitations (magnons) in 1D $XX$ spin chains representing spin waveguides. While Markovian quantum network theory eliminates quantum channels as structureless reservoirs in a Born-Markov approximation to obtain a master equation for the nodes, we are interested in non-Markovian dynamics. This arises from the nonlinear character of the dispersion with band-edge effects, and from finite spin propagation velocities leading to time delays in interactions. To account for the non-Markovian dynamics we treat the quantum degrees of freedom of the nodes and connecting channels as a composite spin system with the surrounding of the quantum network as a Markovian bath, allowing for an efficient solution with time-dependent density matrix renormalization group techniques. We illustrate our approach showing non-Markovian effects in the driven-dissipative formation of quantum dimers, and we present examples for quantum information protocols involving quantum state transfer with engineered elements as basic building blocks of quantum spintronic circuits.

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Tomás Ramos, Benoît Vermersch, Philipp Hauke, Hannes Pichler, Peter Zoller. 2016-06-23. Non-Markovian Dynamics in Chiral Quantum Networks with Spins and Photons. https://doi.org/10.1103/physreva.93.062104

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