arXiv subjects

Zhaoxi Xiong

Publications and source records attributed to Zhaoxi Xiong.

3 recordsLinked to original sources

arXiv2013

Realization of a Josephson Switch

It has been proposed that intermittent weak links between spontaneously broken symmetry systems can give rise to a novel type of time crystal. Here a practical construction is analyzed in greater detail. For a film-geometry Josephson junction, an applied magnetic field in the junction region can effectively switch on and off the supercurrent. By tuning experimental parameters, one can possibly let the free energy be arbitrarily close to the equilibrium without compromising the life time. A parallel construction for superfluid $^4$He is also proposed.

cond-mat.supr-con↗

arXiv2013

General method for finding ground state manifold of classical Heisenberg model

We investigate classical Heisenberg models with the translation symmetries of infinite crystals. We prove a spiral theorem, which states that under certain conditions there must exist spiral ground states, and propose a natural classification of all manageable models based on some "spectral properties," which are directly related to their ground state manifolds. We demonstrate how the ground state manifold can be calculated analytically for all spectra with finite number of minima and some with extensive minima, and algorithmically for the others. We also extend the method to particular anisotropic interactions.

cond-mat.stat-mech↗

arXiv2012

Models of Topology Change

We show how changes in unitarity-preserving boundary conditions allow continuous interpolation among the Hilbert spaces of quantum mechanics on topologically distinct manifolds. We present several examples, including a computation of entanglement entropy production. We discuss approximate realization of boundary conditions through appropriate interactions, thus suggesting a route to possible experimental realization. We give a theoretical application to quantization of singular Hamiltonians, and give tangible form to the "many worlds" interpretation of wave functions.

hep-th↗