Search Results - "Ogata, Yoshiko"

A Z2-Index of Symmetry Protected Topological Phases with Time Reversal Symmetry for Quantum Spin Chains by Ogata, Yoshiko

“…We introduce a Z 2 -index for time reversal invariant Hamiltonians with unique gapped ground state on quantum spin chains. We show this is an invariant of a C…”
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Boundary States of a Bulk Gapped Ground State in 2-D Quantum Spin Systems by Ogata, Yoshiko

“…We introduce a natural mathematical definition of boundary states of a bulk gapped ground state in the operator algebraic framework of 2-D quantum spin…”
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An Invariant of Symmetry Protected Topological Phases with On-Site Finite Group Symmetry for Two-Dimensional Fermion Systems by Ogata, Yoshiko

“…We consider SPT-phases with on-site finite group G symmetry for two-dimensional Fermion systems. We derive an invariant of the classification…”
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A Z2-index of Symmetry Protected Topological Phases with Reflection Symmetry for Quantum Spin Chains by Ogata, Yoshiko

“…For the classification of SPT phases, defining an index is a central problem. In the famous paper  (Pollmann et al. Phys Rev B 81:064439, 2010), Pollmann,…”
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Type of Local von Neumann Algebras in Abelian Quantum Double Models by Ogata, Yoshiko

“…We show that the local von Neumann algebra on convex areas of the frustration-free ground state of abelian quantum double models is of type I I ∞ …”
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A Class of Asymmetric Gapped Hamiltonians on Quantum Spin Chains and its Characterization III by Ogata, Yoshiko

“…In this paper, we consider the classification problem of asymmetric gapped Hamiltonians, which are given as the non-degenerate part of the Hamiltonians…”
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A Class of Asymmetric Gapped Hamiltonians on Quantum Spin Chains and its Characterization I by Ogata, Yoshiko

“…We introduce a class of gapped Hamiltonians on quantum spin chains, which allows asymmetric edge ground states. This class is an asymmetric generalization of…”
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A Class of Asymmetric Gapped Hamiltonians on Quantum Spin Chains and its Characterization II by Ogata, Yoshiko

“…We give a characterization of the class of gapped Hamiltonians introduced in Part I (Ogata, A class of asymmetric gapped Hamiltonians on quantum spin chains…”
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A classification of pure states on quantum spin chains satisfying the split property with on-site finite group symmetries by Ogata, Yoshiko

“…We consider a set SPG(\mathcal {A}) of pure split states on a quantum spin chain \mathcal {A} which are invariant under the on-site action \tau of a finite…”
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The Split and Approximate Split Property in 2D Systems: Stability and Absence of Superselection Sectors by Naaijkens, Pieter, Ogata, Yoshiko

“…The split property of a pure state for a certain cut of a quantum spin system can be understood as the entanglement between the two subsystems being weak. From…”
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An $H^{3}(G,{\mathbb T})$-valued index of symmetry-protected topological phases with on-site finite group symmetry for two-dimensional quantum spin systems by Ogata, Yoshiko

“…We consider symmetry-protected topological phases with on-site finite group G symmetry $\beta $ for two-dimensional quantum spin systems. We show that they…”
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General Lieb–Schultz–Mattis Type Theorems for Quantum Spin Chains by Ogata, Yoshiko, Tachikawa, Yuji, Tasaki, Hal

“…We develop a general operator algebraic method which focuses on projective representations of symmetry group for proving Lieb–Schultz–Mattis type theorems,…”
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The classification of symmetry protected topological phases of one-dimensional fermion systems by Bourne, Chris, Ogata, Yoshiko

“…We introduce an index for symmetry-protected topological (SPT) phases of infinite fermionic chains with an on-site symmetry given by a finite group G. This…”
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General Lieb–Schultz–Mattis Type Theorems for Quantum Spin Chains by Ogata, Yoshiko, Tachikawa, Yuji, Tasaki, Hal

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A Generalization of Powers–Størmer Inequality by Ogata, Yoshiko

“…In this note, we prove the following inequality: , where and η are positive normal linear functionals over a von Neumann algebra. This is a generalization of…”
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C 1-Classification of Gapped Parent Hamiltonians of Quantum Spin Chains by Bachmann, Sven, Ogata, Yoshiko

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Lieb–Schultz–Mattis Type Theorems for Quantum Spin Chains Without Continuous Symmetry by Ogata, Yoshiko, Tasaki, Hal

“…We prove that a quantum spin chain with half-odd-integral spin cannot have a unique ground state with a gap, provided that the interaction is short ranged,…”
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A $${{\mathbb {Z}}}_2$$-index of Symmetry Protected Topological Phases with Reflection Symmetry for Quantum Spin Chains by Ogata, Yoshiko

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Remote extraction and destruction of spread qubit information by Ogata, Yoshiko, Murao, Mio

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A $${{\mathbb {Z}}}_2$$-Index of Symmetry Protected Topological Phases with Time Reversal Symmetry for Quantum Spin Chains by Ogata, Yoshiko

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