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Title: Ultracold Atoms in a Disordered Crystal of Light: Towards a Bose Glass

Abstract

We use a bichromatic optical lattice to experimentally realize a disordered system of ultracold strongly interacting {sup 87}Rb bosons. In the absence of disorder, the atoms are pinned by repulsive interactions in the sites of an ideal optical crystal, forming one-dimensional Mott-insulator states. We measure the excitation spectrum of the system as a function of disorder strength and characterize its phase-coherence properties with a time-of-flight technique. Increasing disorder, we observe a broadening of the Mott-insulator resonances and the transition to a state with vanishing long-range phase coherence and a flat density of excitations, which suggest the formation of a Bose-glass phase.

Authors:
; ; ; ;  [1]
  1. LENS European Laboratory for Nonlinear Spectroscopy and Dipartimento di Fisica, Universita di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (Italy)
Publication Date:
OSTI Identifier:
20951171
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevLett.98.130404; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMS; BOSONS; CRYSTALS; EXCITATION; GLASS; ONE-DIMENSIONAL CALCULATIONS; RUBIDIUM 87; TIME-OF-FLIGHT METHOD

Citation Formats

Fallani, L., Lye, J. E., Guarrera, V., Fort, C., and Inguscio, M.. Ultracold Atoms in a Disordered Crystal of Light: Towards a Bose Glass. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.130404.
Fallani, L., Lye, J. E., Guarrera, V., Fort, C., & Inguscio, M.. Ultracold Atoms in a Disordered Crystal of Light: Towards a Bose Glass. United States. doi:10.1103/PHYSREVLETT.98.130404.
Fallani, L., Lye, J. E., Guarrera, V., Fort, C., and Inguscio, M.. Fri . "Ultracold Atoms in a Disordered Crystal of Light: Towards a Bose Glass". United States. doi:10.1103/PHYSREVLETT.98.130404.
@article{osti_20951171,
title = {Ultracold Atoms in a Disordered Crystal of Light: Towards a Bose Glass},
author = {Fallani, L. and Lye, J. E. and Guarrera, V. and Fort, C. and Inguscio, M.},
abstractNote = {We use a bichromatic optical lattice to experimentally realize a disordered system of ultracold strongly interacting {sup 87}Rb bosons. In the absence of disorder, the atoms are pinned by repulsive interactions in the sites of an ideal optical crystal, forming one-dimensional Mott-insulator states. We measure the excitation spectrum of the system as a function of disorder strength and characterize its phase-coherence properties with a time-of-flight technique. Increasing disorder, we observe a broadening of the Mott-insulator resonances and the transition to a state with vanishing long-range phase coherence and a flat density of excitations, which suggest the formation of a Bose-glass phase.},
doi = {10.1103/PHYSREVLETT.98.130404},
journal = {Physical Review Letters},
number = 13,
volume = 98,
place = {United States},
year = {Fri Mar 30 00:00:00 EDT 2007},
month = {Fri Mar 30 00:00:00 EDT 2007}
}
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