10 citations · 26 across the 15 of their papers we have counts for
15 papers
Absence of nontrivial local conserved quantities in a class of -symmetric spin-1 chains
Shunsuke Sengoku, Haruki Watanabe
We prove the absence of nontrivial local conserved quantities in a class of -symmetric spin- chains with nearest-neighbor interactions in which some of the quadrupolar cou…
Distinct finite-temperature phase diagrams of non-invertible Kennedy--Tasaki duals
Weiguang Cao, Haruki Watanabe
Do two Hamiltonians related by a non-invertible transformation necessarily share the same finite-temperature phase diagram? For a cluster-model interpolation and its Kennedy…
Quantized topological invariant of symmetry-projected Gibbs states
Weiguang Cao, Haruki Watanabe
We study Gibbs states projected onto the symmetric sector of contractible one-form symmetries. In a three-dimensional cluster-model interpolation, this projection stabilizes symmet…
Gibbs-state phases beyond microscopic symmetry breaking: A phase invariant for the 3D toric code
Haruki Watanabe
Do phases of Gibbs states admit a classification beyond symmetry breaking? We study the three-dimensional toric code with transverse and longitudinal fields that explicitly break b…
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…
Quasi-local Frustration-Free Free Fermions
Shunsuke Sengoku, Hoi Chun Po, Haruki Watanabe
Recent studies have revealed that frustration-free models, expressed as sums of finite-range interactions or hoppings, exhibit several properties markedly different from those of f…
Frustration-free free fermions
Seishiro Ono, Rintaro Masaoka, Haruki Watanabe +1
We develop a general theory of frustration-free free-fermion systems and derive the necessary and sufficient conditions for such Hamiltonians. Assuming locality and translation inv…
Frustration-free free fermions and beyond
Rintaro Masaoka, Seishiro Ono, Hoi Chun Po +1
Frustration-free Hamiltonians provide pivotal models for understanding quantum many-body systems. In this paper, we establish a general framework for frustration-free fermionic sys…
Rigorous lower bound of the dynamical critical exponent of the Ising model
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
We study the kinetic Ising model under Glauber dynamics and establish an upper bound on the spectral gap for finite systems. This bound implies the critical exponent inequality $z…
Rigorous lower bound on dynamical exponents in gapless frustration-free systems
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
This work rigorously establishes a universal lower bound for the dynamical exponent in frustration-free quantum many-body systems whose ground states exhibit power-law deca…
Quadratic dispersion relations in gapless frustration-free systems
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
Recent case-by-case studies revealed that the dispersion of low energy excitations in gapless frustration-free Hamiltonians is often quadratic or softer. In this work, we argue tha…
Spontaneous breaking of U(1) symmetry at zero temperature in one dimension
Haruki Watanabe, Hosho Katsura, Jong Yeon Lee
The Hohenberg--Mermin--Wagner theorem states that there is no spontaneous breaking of continuous symmetries in spatial dimensions at finite temperature. At zero temperatur…