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arXiv · 0910.1322

Universal phase diagram of disordered bosons from a doped quantum magnet

Rong Yu·Stephan Haas·Tommaso Roscilde
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Abstract

A quantum particle cannot in general diffuse through a disordered medium because of its wavelike nature, but interacting particles can escape localization by collectively percolating through the system. For bosonic particles this phenomenon corresponds to a quantum transition from a localized insulator phase - the Bose glass - to a superfluid phase, in which particles condense into an extended state. Here, we construct a universal phase diagram of disordered bosons in doped quantum magnets for which bosonic quasi-particles are represented by magnetized states (spin triplets) of the quantum spins, condensing into a magnetically ordered state. The appearance of a Bose glass leads to strong measurable signatures in the onset of superfluidity of the spin-triplet gas, exhibiting a complex crossover from low-temperature quantum percolation to a conventional condensation transition at intermediate temperatures.

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Rong Yu, Stephan Haas, Tommaso Roscilde. 2009-10-07. Universal phase diagram of disordered bosons from a doped quantum magnet. https://doi.org/10.1209/0295-5075%2F89%2F10009

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