arXiv subjects

C. -H. Hsueh

Publications and source records attributed to C. -H. Hsueh.

5 recordsLinked to original sources

arXiv2017

Turbulence scaling laws across the superfluid to supersolid transition

We investigate quantum turbulence in a two-dimensional trapped supersolid and demonstrate that both the wave and vortex turbulence involve triple rather than dual cascades, as in a superfluid. Because of the presence of a second gapless mode associated with translation symmetry breaking, a new $k^{-13/3}$ scaling law is predicted to occur in the wave turbulence. Simultaneous fast vortex-antivortex creation and annihilation in the interior of the oscillating supersolid results in a $k^{-1}$ scaling law in the vortex turbulence. Numerical simulations based on the Gross-Pitaevskii equation confirmed the predictions.

cond-mat.quant-gas↗

arXiv2013

Spin orders in the supersolid phases in binary Rydberg-dressed Bose-Einstein condensates

We show that the five possible ordered states in a quantum spin-1/2 system with long-range exchange interactions: Neel, ladder, Peierls, coincidence, and domain states, can be realized in a binary Rydberg-dressed BEC system in the supersolid phase. In such a system, blockade phenomenon is shown to also occur for pairs of different excited-state atoms, which results in similar intra- and inter-species long-range interactions between ground-state atoms. It suggests that a pseudo spin-1/2 system can be possibly formed in the ground state of ultracold rudibium.

cond-mat.quant-gas↗

arXiv2011

Quantum crystals in a trapped Rydberg-dressed Bose-Einstein condensate

Spontaneously crystalline ground states, called quantum crystals, of a trapped Rydberg-dressed Bose-Einstein condensate are numerically investigated. As a result described by a mean-field order parameter, such states simultaneously possess crystalline and superfluid properties. A hexagonal droplet lattice is observed in a quasi-two-dimensional system when dressing interaction is sufficiently strong. Onset of these states is characterized by a drastic drop of the non-classical rotational inertia proposed by Leggett [Phys. Rev. Lett. 25, 1543 (1970)]. In addition, an AB stacking bilayer lattice can also be attained. Due to an anisotropic interaction possibly induced by an external electric field, transition from a hexagonal to a nearly square droplet lattice is also observed.

cond-mat.quant-gas↗

arXiv2011

Equilibrium vortex formation in ultrarapidly rotating two-component Bose-Einstein condensates

Equilibrium vortex formation in rotating binary Bose gases with a rotating frequency higher than the harmonic trapping frequency is investigated theoretically. We consider the system being evaporatively cooled to form condensates and a combined numerical scheme is applied to ensure the binary system being in an authentic equilibrium state. To keep the system stable against the large centrifugal force of ultrafast rotation, a quartic trapping potential is added to the existing harmonic part. Using the Thomas-Fermi approximation, a critical rotating frequency Ω_c is derived, which characterizes the structure with or without a central density hole. Vortex structures are studied in detail with rotation frequency both above and below ?Ω_c and with respect to the miscible, symmetrically separated, and asymmetrically separated phases in their nonrotating ground-state counterparts.

cond-mat.quant-gas↗

arXiv2011

Spontaneous Crystallization of Skyrmions and Fractional Vortices in the Fast-rotating and Rapidly-quenched Spin-1 Bose-Einstein Condensates

We investigate the spontaneous generation of crystallized topological defects via the combining effects of fast rotation and rapid thermal quench on the spin-1 Bose-Einstein condensates. By solving the stochastic projected Gross-Pitaevskii equation, we show that, when the system reaches equilibrium, a hexagonal lattice of skyrmions, and a square lattice of half-quantized vortices can be formed in a ferromagnetic and antiferromagnetic spinor BEC, respetively, which can be imaged by using the polarization-dependent phase-contrast method.

cond-mat.quant-gas↗