collaborators

7 papers

quant-ph2019

Deformations of the Boundary Theory of the Square Lattice AKLT Model

John Martyn, Kohtaro Kato, Angelo Lucia

The 1D AKLT model is a paradigm of antiferromagnetism, and its ground state exhibits symmetry-protected topological order. On a 2D lattice, the AKLT model has recently gained atten…

quant-ph2019

Toy model of boundary states with spurious topological entanglement entropy

Kohtaro Kato, Fernando G. S. L. Brandão

Topological entanglement entropy has been extensively used as an indicator of topologically ordered phases. We study the conditions needed for two-dimensional topologically trivial…

quant-ph2019

Clustering of conditional mutual information for quantum Gibbs states above a threshold temperature

Tomotaka Kuwahara, Kohtaro Kato, Fernando G. S. L. Brandão

We prove that the quantum Gibbs states of spin systems above a certain threshold temperature are approximate quantum Markov networks, meaning that the conditional mutual informatio…

quant-ph2019

Macroscopic Thermodynamic Reversibility in Quantum Many-Body Systems

Philippe Faist, Takahiro Sagawa, Kohtaro Kato +2

The resource theory of thermal operations, an established model for small-scale thermodynamics, provides an extension of equilibrium thermodynamics to nonequilibrium situations. On…

cond-mat.str-el2019

Fusion rules from entanglement

Bowen Shi, Kohtaro Kato, Isaac H. Kim

We derive some of the axioms of the algebraic theory of anyon [A. Kitaev, Ann. Phys., 321, 2 (2006)] from a conjectured form of entanglement area law for two-dimensional gapped sys…

quant-ph2018

An entropic invariant for 2D gapped quantum phases

Kohtaro Kato, Pieter Naaijkens

We introduce an entropic quantity for two-dimensional (2D) quantum spin systems to characterize gapped quantum phases modeled by local commuting projector code Hamiltonians. The de…