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arXiv · 1411.2489

How two spins can thermalize a third spin

Stephan Kleinbölting·Rochus Klesse
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Abstract

We consider thermalization of a microscopic quantum system by interaction with a thermal bath. Our interest is the minimal size the bath can have while still being able to thermalize the system. Within a specific thermalization scheme we show that a single spin-1/2 can be fully thermalized by interaction with a bath that consists of just two other spin-1/2. The two bath spins are initially in a pure, entangled state, and the thermalizing interaction is a Heisenberg exchange-interaction of the system-spin with one of the bath spins. The time dependent coupling strength has to obey a single integral constraint. We also present a simple generalization of this minimal model in which the bath consists of an arbitrary number of spin-1/2 pairs.

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Stephan Kleinbölting, Rochus Klesse. 2014-11-10. How two spins can thermalize a third spin. https://doi.org/10.1103/physreve.91.052101

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