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arXiv · 2011.06279

Anderson localization of composite particles

Fumika Suzuki·Mikhail Lemeshko·Wojciech H. Zurek·Roman V. Krems
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Abstract

We investigate the effect of coupling between translational and internal degrees of freedom of composite quantum particles on their localization in a random potential. We show that entanglement between the two degrees of freedom weakens localization due to the upper bound imposed on the inverse participation ratio by purity of a quantum state. We perform numerical calculations for a two-particle system bound by a harmonic force in a 1D disordered lattice and a rigid rotor in a 2D disordered lattice. We illustrate that the coupling has a dramatic effect on localization properties, even with a small number of internal states participating in quantum dynamics.

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Fumika Suzuki, Mikhail Lemeshko, Wojciech H. Zurek, Roman V. Krems. 2021-06-14. Anderson localization of composite particles. https://doi.org/10.1103/physrevlett.127.160602

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