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arXiv · 1801.01445

Detection of a Disorder-Induced Bose-Einstein Condensate in a Quantum Spin Material at High Magnetic Fields

A. Orlova·H. Mayaffre·S. Krämer·M. Dupont·S. Capponi·N. Laflorencie·A. Paduan-Filho·M. Horvatić
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Abstract

The coupled spin-1 chains material NiCl$_2$-4SC(NH$_2$)$_2$ (DTN) doped with Br impurities is expected to be a perfect candidate for observing many-body localization at high magnetic field: the so-called "Bose glass", a zero-temperature bosonic fluid, compressible, gapless, incoherent, and short-range correlated. Using nuclear magnetic resonance (NMR), we critically address the stability of the Bose glass in doped DTN, and find that it hosts a novel disorder-induced ordered state of matter, where many-body physics leads to an unexpected resurgence of quantum coherence emerging from localized impurity states. An experimental phase diagram of this new "order-from-disorder" phase, established from NMR $T_1^{-1}$ relaxation rate data in the (13 $\pm$ 1)% Br-doped DTN, is found to be in excellent agreement with the theoretical prediction from large-scale quantum Monte Carlo simulations.

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A. Orlova, H. Mayaffre, S. Krämer, M. Dupont, S. Capponi, N. Laflorencie, A. Paduan-Filho, M. Horvatić. 2018-01-04. Detection of a Disorder-Induced Bose-Einstein Condensate in a Quantum Spin Material at High Magnetic Fields. https://doi.org/10.1103/physrevlett.121.177202

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