19 citations · 35 across the 10 of their papers we have counts for
10 papers
Split Property and Fermionic String Order
Taku Matsui
We show split property of gapped ground states for Fermion systems on a one-dimensional lattice and clarify mathematical meaning of string order of fermions.
KMS States of Weakly Coupled Anharmonic Crystals and the Resolvent CCR Algebra
T. Kanda, Taku Matsui
We consider equilibrium states of weakly coupled anharmonic quantum oscillators on Z. We consider the Resolvent CCR Algebra introduced by D.Buchholtz and H.Grundling, and we show t…
Kakutani Dichotomy on Free States
Taku Matsui, Shigeru Yamagami
Two quasi-free states on a CAR or CCR algebra are shown to generate quasi-equivalent representations unless they are disjoint.
Boundedness of Entanglement Entropy,and Split Property of Quantum Spin Chains
Taku Matsui
We show the boundedness of entanglement entropy for (bipartite) pure states of quantum spin chains implies split property of subsystems. As a corollary the infinite volume ground s…
On Spectral Gap,U(1) Symmetry and Split Property in Quantum Spin Chains
Taku Matsui
We consider a class of ground states for quantum spin chains on an integer lattice. First we show that presence of the spectral gap between the ground state energy and the rest of…
On Haag Duality for Pure States of Quantum Spin Chain
M. Keyl, Taku Matsui, D. Schlingemann +1
We consider quantum spin chains and their translationally invariant pure states. We prove Haag duality for quasilocal observables localized in semi-infinite intervals when the von…