We derive a uniformly frustrated $XY$ model that describes two-dimensional Josephson-junction arrays consisting of rotating Bose-Einstein condensates trapped by both a harmonic trap and a corotating deep optical lattice. The harmonic trap makes the coupling constant of the model have a nonuniform parabolic dependance. We study the ground state through Monte Carlo simulations in a wide range of the frustration parameter $f$, revealing a rich variety of vortex patterns.
Cooper quartets and fractional vortices in frustrated Josephson junction dice arrays
University of Cologne(科隆大学);Forschungszentrum Jülich GmbH, Institute of Quantum Control, Peter Grünberg Institut (PGI-8)(于利希研究中心有限公司,量子控制研究所,彼得·格林贝格研究所(PGI-8));University of Oslo(奥斯陆大学);Università di Pisa(比萨大学);INFN, Sezione di Pisa(意大利国家核物理研究所,比萨分部)
Fully frustrated Josephson junction ladders with Mobius boundary conditions as topologically protected qubits
我们展示了如何通过使用具有Mobius边界条件的完全阻挫的约瑟夫森结阶梯(JJL)来实现“受保护”的量子比特。这种系统最近已经在扭曲共形场论(CFT)方法(Mod. Phys. Lett. A 15(2000)1679; Nucl.Phys.B641(2002)547),并且显示出发展通量分级现象(Eur. J. B 49(2006)83)。在将系统的基态的拓扑性质与半通量量子的存在联系起来时,充分利用了“闭合”几何的相关性,并预测了拓扑秩序的出现(JSTAT(2005)P03006)。本文分析了基态在绝热磁通量变化下的稳定性和变换性质,并提出了实现防止退相干的固态量子比特的深刻后果。
Quantum work statistics and coherence effects in quenched bosonic Josephson junctions
Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO)(意大利国家光学研究所);European Laboratory for Non-linear Spectroscopy, Università di Firenze(佛罗伦萨大学欧洲非线性光谱学实验室);Department of Physics and Astronomy, University of Florence(佛罗伦萨大学物理与天文学系)
Bosonic Working Media in a Frustrated Rhombi Chain: Otto and Stirling Cycles from Flat Bands, Caging, and Flux Control
Facultad de Ingeniería, Universidad San Sebastián(圣塞巴斯蒂安大学工程学院);Departamento de Física, Universidad Técnica Federico Santa María(智利技术费德里科·萨马拉大学物理系);Department of Physics, Universitat Autònoma de Barcelona(巴塞罗那自治大学物理系);Instituto de Física, Pontificia Universidad Católica de Valparaíso(天主教瓦尔帕莱索大学物理研究所);Physical and Computational Sciences,Pacific Northwest National Laboratory(太平洋西北国家实验室物理与计算科学部);Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile(智利大学物理与数学科学学院物理系)