Shijie Hu

Multistep approach to microscopic models for frustrated quantum magnets: the case of the natural mineral azurite.

The natural mineral azurite Cu(3)(CO(3))(2)(OH)(2) is a frustrated magnet displaying unusual and controversially discussed magnetic behavior. Motivated by the lack of a unified description for this system, we perform a theoretical study based on density functional theory as well as state-of-the-art numerical many-body calculations. We propose an effective generalized spin-1/2 diamond chain model which provides a consistent description of experiments: low-temperature magnetization, inelastic neutron scattering, nuclear magnetic resonance measurements, magnetic susceptibility as well as new specific heat measurements. With this study we demonstrate that the balanced combination of first principles with powerful many-body methods successfully describes the behavior of this frustrated material.

Accurate determination of the Gaussian transition in spin-1 chains with single ion Anisotropy

The Gaussian transition in the spin-one Heisenberg chain with single-ion anisotropy is extremely difficult to treat, both analytically and numerically. We introduce an improved DMRG procedure with strict error control, which we use to access very large systems. By considering the bulk entropy, we determine the Gaussian transition point to 4-digit accuracy,

Ground-state phase diagram of an anisotropic spin-

D_{c}/J = 0.96845(8)

\frac{1}{2}

, resolving a long-standing debate in quantum magnetism. With this value, we obtain high-precision data for the critical behavior of quantities including the ground-state energy, gap, and transverse string-order parameter, and for the critical exponent,

model on the triangular lattice

\nu = 1.472(2)

Evolution of magnetic structure driven by synthetic spin-orbit coupling in a two-component Bose-Hubbard model

. Applying our improved technique at

Ferromagnetism in a two-component Bose-Hubbard model with synthetic spin-orbit coupling

J_{z} = 0.5

Symmetry-Protected Topological Phase in a One-Dimensional Correlated Bosonic Model with a Synthetic Spin-Orbit Coupling.

highlights essential differences in critical behavior along the Gaussian transition line.

Thermodynamics of a spin-12XYZ Heisenberg chain with a Dzyaloshinskii-Moriya interaction

Motivated by the recent experiment on a rare-earth material YbMgGaO

Low-energy properties of anisotropic two-dimensional spin-1/2 Heisenberg models in staggered magnetic fields

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