Seji Kang

Observation of a geometric Hall effect in a spinor Bose-Einstein condensate with a Skyrmion spin texture.

For a spin-carrying particle moving in a spatially varying magnetic field, effective electromagnetic forces can arise due to the geometric phase associated with adiabatic spin rotation of the particle. We report the observation of a geometric Hall effect in a spinor Bose-Einstein condensate with a Skyrmion spin texture. Under translational oscillations of the spin texture, the condensate resonantly develops a circular motion in a harmonic trap, demonstrating the existence of an effective Lorentz force. When the condensate circulates, quantized vortices are nucleated in the boundary region of the condensate and the vortex number increases over 100 without significant heating. We attribute the vortex nucleation to the shearing effect of the effective Lorentz force from the inhomogeneous effective magnetic field.

Emergence and scaling of spin turbulence in quenched antiferromagnetic spinor Bose-Einstein condensates

We investigate the phase-transition dynamics of a quasi-two-dimensional antiferromagnetic spin-1 Bose-Einstein condensate from the easy-axis polar phase to the easy-plane polar phase, which is initiated by suddenly changing the sign of the quadratic Zeeman energy

Collisional Dynamics of Half-Quantum Vortices in a Spinor Bose-Einstein Condensate.

q

Erratum: Half-Quantum Vortices in an Antiferromagnetic Spinor Bose-Einstein Condensate [Phys. Rev. Lett. 115, 015301 (2015)].

. We observe the emergence and decay of spin turbulence and the formation of half-quantum vortices (HQVs) in the quenched condensate. The characteristic time and length scales of the turbulence generation dynamics are proportional to

Rotating a Bose-Einstein condensate by shaking an anharmonic axisymmetric magnetic potential

{|q|}^{\ensuremath{-}1/2}

Half-Quantum Vortices in an Antiferromagnetic Spinor Bose-Einstein Condensate.

as inherited from the dynamic instability of the initial state. In the evolution of the spin turbulence, spin-wave excitations develop from large to small length scales, suggesting a direct energy cascade, and the spin population for the axial polar domains exhibit a nonexponential decay. The final equilibrated condensate contains HQVs, and the number is found to increase and saturate with increasing

Metastable polar state of a spin-1 antiferromagnetic Bose-Einstein condensate under a magnetic field gradient

|q|

Quench Dynamics of Quasi-2D Antiferromagnetic Spinor Condensates

. Our results demonstrate the time-space scaling properties of the phase-transition dynamics near the critical point and the peculiarities of the spin-turbulence state of the antiferromagnetic spinor condensate.

Collision of Half-Quantum Vortices in a Spinor Bose-Einstein Condensate

We present an experimental study on the interaction and dynamics of half-quantum vortices (HQVs) in an antiferromagnetic spinor Bose-Einstein condensate. By exploiting the orbit motion of a vortex dipole in a trapped condensate, we perform a collision experiment of two HQV pairs, and observe that the scattering motions of the HQVs is consistent with the short-range vortex interaction that arises from nonsingular magnetized vortex cores. We also investigate the relaxation dynamics of turbulent condensates containing many HQVs, and demonstrate that spin wave excitations are generated by the collisional motions of the HQVs. The short-range vortex interaction and the HQV-magnon coupling represent two characteristics of the HQV dynamics in the spinor superfluid.

Observation of half-quantum vortices in an antiferromagnetic spinor Bose-Einstein condensate

We have found that one of the details on the spin-dependent phase-contrast imaging method is incorrectly presented in the text. The frequency of the probe light was detuned by −20 MHz from the 3S1=2jF 1⁄4 1i → 3P3=2jF0 1⁄4 2i transition, not the 3S1=2jF 1⁄4 1i → 3P1=2jF0 1⁄4 2i transition. In the abstract and the text, the gapless magnon excitations associated with the observed spin fluctuations are described as transverse, but they should be referred to as axial magnons [1]. We observed no population of themz 1⁄4 0 component in the antiferromagnetic phase. This nomenclatural correction dose not affect the results and conclusion of the Letter.