title: Tunable atomic spin-orbit coupling synthesized with a modulating gradient magnetic field.
abstract: We report the observation of synthesized spin-orbit coupling (SOC) for ultracold spin-1 (87)Rb atoms. Different from earlier experiments where a one dimensional (1D) atomic SOC of pseudo-spin-1/2 is synthesized with Raman laser fields, the scheme we demonstrate employs a gradient magnetic field (GMF) and ground-state atoms, thus is immune to atomic spontaneous emission. The strength of SOC we realize can be tuned by changing the modulation amplitude of the GMF, and the effect of the SOC is confirmed through the studies of: 1) the collective dipole oscillation of an atomic condensate in a harmonic trap after the synthesized SOC is abruptly turned on; and 2) the minimum energy state at a finite adiabatically adjusted momentum when SOC strength is slowly ramped up. The condensate coherence is found to remain very good after driven by modulating GMFs. Our scheme presents an alternative means for studying interacting many-body systems with synthesized SOC.
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Lingna
authors.initials: L
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Jiyao
authors.initials: J
authors.lastname: Chen
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Guan
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Kuiyi
authors.initials: K
authors.lastname: Gao
authors.affiliation: MOE Key Laboratory of Fundamental Physical Quantities Measurements, School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Zhi-Fang
authors.initials: ZF
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: You
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Ruquan
authors.initials: R
authors.lastname: Wang