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Chinese Physics B 2009年第11期18卷 4924-4931页

作者：张冰志崔虎李湘衡佘卫龙 State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University

We theoretically study the beam dynamical behaviour in a modulated optical lattice with a quadratic potential in a photovoltaic photorefractive crystal. We find that two different bloch oscillation patterns appear for the excitation of both broad and narrow light beams. One kind of optical Landau-Zener tunnelling also appears upon the bloch oscillation and can be controlled by adjusting the parameter of the optical lattice. Unlike the case of linear potential, the energy radiation due to Landau-Zener tunnelling can be confined in modulated lattices of this kind. For high input intensity levels, the Landau-Zener tunnelling is suppressed by the photovoltaic photorefractive nonlinearity and a symmetry breaking of beam propagation from the modulational instability appears.

关键词： bloch oscillation Landau-Zener tunnelling double-period lattice photovoltaic photore- fractive

Electromagnetic bloch oscillation in one-dimensional multiple microcavities composed of metamaterials

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Chinese Physics B 2014年第4期23卷 246-250页

作者：王同标刘念华于天宝邓新华徐旭明廖清华 Department of Physics Nanchang University Institute for Advanced Study Nanchang University

We propose a photonic structure stacked sequentially by one-dimensional photonic crystals and cavities. The whole structure is composed of single-negative and double-negative materials. The optical Wannier-Stark ladder （WSL） can be obtained in a low frequency region by modulating the widths of the cavities in order. We simulate the dynamical behavior of the electromagnetic wave passing through the proposed photonic structure. Due to the dispersive characteristics of the metamaterials, a very narrow WSL can be obtained. The long-period electromagnetic bloch oscillation is demonstrated theoretically to have a period on a microsecond time scale.

关键词： bloch oscillation metamaterial

Schrodinger cat states prepared by bloch oscillation in a spin-dependent optical lattice

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1810-1814页

作者： WU BaoJun ZHANG JiangMin Beijing National Laboratory for Condensed Matter Physics Institute of PhsicsChinese Academy of SciencesBeijing 100080China

We propose to use bloch oscillation of ultra-cold atoms in a spin-dependent optical lattice to prepare Schro¨dinger cat *** on its internal state,an atom feels different periodic potentials and thus has different energy band structures for its center-of-mass ***,under the same gravity force,the wave packets associated with different internal states perform bloch oscillation of different amplitudes in space and in particular they can be macroscopically displaced with respect to each *** this manner,a cat state can be prepared.

关键词： bloch oscillation Schrodinger cat spin-dependent optical lattice

Tunneling dynamics of bosons in the diamond lattice chain

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Chinese Physics B 2018年第10期27卷 440-448页

作者： Na-Na Chang Ju-Kui Xue College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070China

We analyze the effect of tilting and artificial magnetic flux, on the energy bands structure for the system and the corresponding tunneling dynamics for bosons with various initial configurations in the diamond lattice chain, where intriguing and significant phenomena occur, including Landau–Zener tunneling, bloch oscillations, and localization *** vertical tilting and artificial magnetic flux may alter the structure of energy levels（dispersion structure or flat band）,and enforce the occurrence of Landau–Zener tunneling, which scans the whole of the bloch bands. We find that, transitions among Landau–Zener tunneling, bloch oscillations, and localization phenomenon, are not only closely related to the energy bands structure, but also depends on the initial configuration of bosons in the diamond lattice chain. As a consequence,Landau–Zener tunneling, bloch oscillations, and localization phenonmenon of bosons always counteract and are complementary with each other in the diamond lattice chain.

关键词： Bose-Einstein condensate Landau-Zener tunneling bloch oscillation localization flat band