Nonlinear response of interacting bosons in a quasiperiodic potential

Article

关键词: ORDER HARMONIC-GENERATION;    ANDERSON LOCALIZATION;    ULTRACOLD ATOMS;    INSULATOR;    TRANSITION;    SUPERFLUID;    ELECTRONS;    1064-NM;    SYSTEM;    FIELD;   

DOI  :  10.1103/PhysRevB.107.035120

来源: SCIE

【 摘 要 】

We theoretically study the electric pulse-driven nonlinear response of interacting bosons loaded in an optical lattice in the presence of an incommensurate superlattice potential. In the noninteracting limit (U = 0), the response of the localized phase differs significantly than the response of the delocalized phases. In particular, we show that the particle current contains only odd harmonics in the delocalized phase in contrast to the localized phase where both even and odd harmonics exist. The relative magnitudes of these even and odd harmonics and the contrast of the peaks can be tuned by varying frequency and the number of cycles of the applied pulse, respectively. In the presence of repulsive interactions, the amplitudes of the even and odd harmonics further depend on the relative strengths of the interaction U and the disorder potential V0. We illustrate that the disorder and interaction-induced phases can be distinguished through the particle current. Finally, we discuss the dynamics of field-induced excitation responsible for exhibiting higher harmonics in the current spectrum.

【 授权许可】

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