NMR quantum simulation of localization effects induced by decoherence

TL;DR

This paper uses NMR quantum simulation to study how decoherence causes localization of quantum information, revealing a dynamic equilibrium size of spin clusters that depends on perturbation strength.

Contribution

It demonstrates how decoherence-induced localization can be simulated and characterized in a nuclear spin quantum system, revealing a quantitative relationship with perturbation strength.

Findings

Localization size decreases with increasing perturbation strength

System reaches a dynamic equilibrium size of spin clusters

Localization effects resemble Anderson localization phenomena

Abstract

The loss of coherence in quantum mechanical superposition states limits the time for which quantum information remains useful. Similarly, it limits the distance over which quantum information can be transmitted, resembling Anderson localization, where disorder causes quantum mechanical states to become localized. Here, we investigate in a nuclear spin-based quantum simulator, the localization of the size of spin clusters that are generated by a Hamiltonian driving the transmission of information, while a variable-strength perturbation counteracts the spreading. We find that the system reaches a dynamic equilibrium size, which decreases with the square of the perturbation strength.