6 papers
Topological Phase Transitions and Their Thermodynamic Fate in Arbitrary- Classical Pyrochlore Spin Ice
Sena Watanabe, Yukitoshi Motome, Haruki Watanabe
We develop a self-contained theoretical framework that classifies the topological phases and critical phenomena of classical pyrochlore magnets with arbitrary spin , subject to…
Monte Carlo Study of the Phase Transition of the Model on a Diamond Lattice
Sena Watanabe, Yukitoshi Motome, Haruki Watanabe
We study the phase transition of the classical model on a diamond lattice by Monte Carlo simulations using the Wolff cluster algorithm. Finite-size scaling (FSS) analysis of t…
Continuous crossover between high-pressure ice phases VII and X driven by monopole screening: a model study
Sena Watanabe, Yukitoshi Motome, Haruki Watanabe
The proton-disordered molecular phase of water ice (ice-VII) and its ultrahigh-pressure non-molecular phase (ice-X) share identical macroscopic crystal symmetry (space group $Pn\ba…
Dualities and Topological Classification of the Pyrochlore Spin Ice
Sena Watanabe, Yukitoshi Motome, Haruki Watanabe
We derive dual descriptions of the trivial paramagnetic, -deconfined, and -confined U(1) Coulomb phases of the pyrochlore spin ice. In the monopol…
Gauge-invariant electromagnetic responses in superconductors
Sena Watanabe, Haruki Watanabe
Gauge invariance is essential for making physically meaningful predictions. In superconductors, mean-field Hamiltonians that explicitly break symmetry often yield gauge-depe…
A gauge-invariant formulation of optical responses in superconductors
Sena Watanabe, Haruki Watanabe
Superconductors are often discussed in the mean-field approximation that breaks symmetry. Since the symmetry underlies the charge conservation, naive application of r…