Searcharxiv⌕ Search

arXiv subjects

Hong-Yu Yang

Publications and source records attributed to Hong-Yu Yang.

7 recordsLinked to original sources
arXiv2007

Topological Order in Projected Wave Functions and Effective Theories of Quantum Antiferromagnets

We study the topological order in RVB state derived from Gutzwiller projection of BCS-like mean field state. We propose to construct the topological excitation on the projected RVB state through Gutzwiller projection of mean field state with inserted $Z_{2}$ flux tube. We prove that all projected RVB states derived from bipartite effective theories, no matter the gauge structure in the mean field ansatz, are positive definite in the sense of the Marshall sign rule, which provides a universal origin for the absence of topological order in such RVB state.

cond-mat.supr-con↗
arXiv2006

Spinon-Holon Recombination in Gutzwiller Projected Wave Functions

The Gutzwiller projection is shown to induce nontrivial correlation between the spinon and the holon in the slave Boson theory of the $t-J$ model. We find this correlation is responsible some subtle differences between the slave Boson mean field theory and the Gutzwiller projected wave function(GWF), among which the particle-hole asymmetry in the quasiparticle weight calculated from the GWF is a particular example.

cond-mat.supr-con↗
arXiv2006

Variational study of the one dimensional t-J model

We find the Gutzwiller projected Fermi sea wave function(GWF) has the correct phase structure to describe the kink nature of the doped holes in the ground state of the one dimensional $t-J$ model. We find the failure of the GWF for general value of $J/t$ and electron density $n$ can be attributed to the residual charge correlation in the ground state. We find such residual charge correlation is well described by a XXZ-type effective Hamiltonian. Based on these observations, a Pfaffian-type variational wave function is proposed and is found to reproduce correctly the global phase diagram and corresponding correlation functions of the one dimensional $t-J$ model, including the Luther-Emery phase in the low electron density and large $J/t$ region.

cond-mat.supr-con↗
arXiv2006

On the Origin of the Tunneling Asymmetry in the Cuprate Superconductors: a variational perspective

Through variational Monte Carlo calculation on Gutzwiller projected wave functions, we study the quasiparticle(qp) weight for adding and removing an electron from a high temperature superconductor. We find the qp weight is particle-hole symmetric at sufficiently low energy. We propose to use the tunneling asymmetry as a tool to study the mechanism of electron incoherence in high temperature superconductors.

cond-mat.supr-con↗
arXiv2005

Spin Charge Recombination in Projected Wave Functions

We find spin charge recombination is a generic feature of projected wave functions. We find this effect is responsible for a series of differences between mean field theory prediction and the result from projected wave functions. We also find spin charge recombination plays an important role in determining the dissipation of supercurrent, the quasiparticle properties and the hole - hole correlation.

cond-mat.supr-con↗