相关论文: Ground state properties of quantum Kagome ice hard…
We review several properties of thermal states of spin Hamiltonians with short range interactions. In particular, we focus on those aspects in which the application of tools coming from quantum information theory has been specially…
We present a large-$S$ study of a quantum spin ice Hamiltonian, introduced by Huang, et al., [PRL 112, 167203 (2014)], on the kagome lattice. This model involves a competition between the frustrating Ising term of classical kagome ice, a…
We present high-precision quantum Monte Carlo results for the S=1/2 XY model on a two-dimensional square lattice, in the ground state as well as at finite temperature. The energy, the spin stiffness, the magnetization, and the…
We derive an effective $Z_2$ gauge theory to describe the quantum kagome ice (QKI) state that has been observed by Carrasquilla $\textit{et. al.}$ in Monte Carlo studies of the $S = 1/2$ kagome XYZ model in a Zeeman field. The numerical…
A new model of localized highly frustrated ferromagnetism is presented: kagome spin ice. By use of analytical and Monte Carlo calculations its massive groundstate entropy is evaluated. Monte Carlo calculations are also used to explore the…
A novel macroscopically degenerate state called kagome ice, which was recently found in a spin ice compound Dy2Ti2O7 in a magnetic field applied along the [111] direction of the cubic unit cell, is studied by specific heat measurements. The…
Precise thermometry is of wide importance in science and technology in general and in quantum systems in particular. Here, we investigate fundamental precision limits for thermometry on cold quantum systems, taking into account constraints…
The search for two dimensional quantum spin liquids, exotic magnetic states with an entangled ground state remaining disordered down to zero temperature, has been a great challenge in frustrated magnetism during the last decades. Recently,…
This thesis contains two results for the low temperature behavior of quantum spin systems. First, we present a lower bound for the spin-1 XXZ chain in finite volumes in terms of the gap of the two-site Hamiltonian. The estimate is derived…
We investigate the classical counterpart of an effective Hamiltonian for a strongly trimerized kagome lattice. Although the Hamiltonian only has a discrete symmetry, the classical groundstate manifold has a continuous global rotational…
A quantum model is considered for $N$ bosons populating two orthogonal single-particle modes with tunable energy separation in the presence of flavour-changing contact interaction. The quantum ground state is well approximated as a coherent…
This paper presents a connection between the topological properties of hardcore bosons and that of magnons in quantum spin magnets. We utilize the Haldane-like hardcore bosons on the honeycomb lattice as an example. We show that this system…
In this paper we explore new ways to study the zero temperature limit of quantum statistical mechanics using Quantum Monte Carlo simulations. We develop a Quantum Monte Carlo method in which one fixes the ground state energy as a parameter.…
We present a comprehensive experimental and theoretical study of the kagome ice Coulomb phase, that explores the fine tuning of critical correlations by applied field, temperature and crystal orientation. The continuous modification of…
We study various properties of bosons in two dimensions interacting only via onsite hardcore repulsion. In particular, we use the lattice spin-wave approximation to calculate the ground state energy, the density, the condensate density and…
Ice states, in which frustrated interactions lead to a macroscopic ground-state degeneracy, occur in water ice, in problems of frustrated charge order on the pyrochlore lattice, and in the family of rare-earth magnets collectively known as…
We investigate pairwise quantum correlation as measured by the quantum discord as well as its classical counterpart in the thermodynamic limit of anisotropic XY spin-1/2 chains in a transverse magnetic field for both zero and finite…
In this study, we reveal nontrivial quantum physics in an infinite-temperature system. By performing an unbiased quantum Monte Carlo simulation, we study a hybrid model composed of hard-core bosons, whose hopping amplitude is mediated by…
Y{0.5}$Ca{0.5}BaCo4O7 contains kagome layers of Co ions, whose spins are strongly coupled according to a Curie-Weiss temperature of -2200 K. At low temperatures, T = 1.2 K, our diffuse neutron scattering study with polarization analysis…
We present new results for the Kondo lattice model of strongly correlated electrons, in 1-, 2-, and 3-dimensions, obtained from high-order linked-cluster series expansions. Results are given for varies ground state properties at…