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Related papers: Generic Local Hamiltonians are Gapless

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We show that ground states of unfrustrated quantum spin-1/2 systems on general lattices satisfy an entanglement area law, provided that the Hamiltonian can be decomposed into nearest-neighbor interaction terms which have entangled excited…

Quantum Physics · Physics 2015-05-20 Niel de Beaudrap , Tobias J. Osborne , Jens Eisert

In this paper we address the question of the existence of a spectral gap in a class of local Hamiltonians. These Hamiltonians have the following properties: their ground states are known exactly; all equal-time correlation functions of…

Strongly Correlated Electrons · Physics 2008-11-27 Michael Freedman , Chetan Nayak , Kirill Shtengel

We investigate bosonic Gaussian quantum states on an infinite cubic lattice in arbitrary spatial dimensions. We derive general properties of such states as ground states of quadratic Hamiltonians for both critical and non-critical cases.…

Quantum Physics · Physics 2012-01-23 Norbert Schuch , J. Ignacio Cirac , Michael M. Wolf

We investigate the power of quantum systems for the simulation of Hamiltonian time evolutions on a cubic lattice under the constraint of translational invariance. Given a set of translationally invariant local Hamiltonians and short range…

Quantum Physics · Physics 2009-11-13 Christina V. Kraus , Michael M. Wolf , J. Ignacio Cirac

Quantum Hamiltonian complexity studies computational complexity aspects of local Hamiltonians and ground states; these questions can be viewed as generalizations of classical computational complexity problems related to local constraint…

Quantum Physics · Physics 2015-03-17 Dorit Aharonov , Itai Arad , Zeph Landau , Umesh Vazirani

We study steady-states of quantum Markovian processes whose evolution is described by local Lindbladians. We assume that the Lindbladian is gapped and satisfies quantum detailed balance with respect to a unique full-rank steady state…

Quantum Physics · Physics 2024-05-17 Raz Firanko , Moshe Goldstein , Itai Arad

We present a class of exactly solvable 2D models whose ground states violate conventional beliefs about entanglement scaling in quantum matter. These beliefs are (i) that area law entanglement scaling originates from local correlations…

Quantum Physics · Physics 2023-05-12 Shankar Balasubramanian , Ethan Lake , Soonwon Choi

Graphs are topological spaces that include broader objects than discretized manifolds, making them interesting playgrounds for the study of quantum phases not realized by symmetry breaking. In particular they are known to support anyons of…

Strongly Correlated Electrons · Physics 2021-10-18 Pramod Padmanabhan , Fumihiko Sugino

Recent results have shown the stability of frustration-free Hamiltonians to weak local perturbations, assuming several conditions. In this paper, we prove the stability of free fermion Hamiltonians which are gapped and local. These free…

Quantum Physics · Physics 2017-06-13 M. B. Hastings

In quantum many-body systems, a Hamiltonian is called an ``extensive entropy generator'' if starting from a random product state the entanglement entropy obeys a volume law at long times with overwhelming probability. We prove that (i) any…

Quantum Physics · Physics 2021-11-08 Yichen Huang

We begin by deriving bounds for the entanglement of a spin with an (adjacent and non-adjacent) interval of spins in an arbitrary pure Finitely Correlated States (FCS). The bounds we derive become exact in the case where one considers the…

Quantum Physics · Physics 2008-07-31 Spyridon Michalakis

We locate gaps in the spectrum of a Hamiltonian on a periodic cuboidal (and generally hyperrectangular) lattice graph with $\delta$ couplings in the vertices. We formulate sufficient conditions under which the number of gaps is finite. As…

Mathematical Physics · Physics 2020-05-26 Ondřej Turek

Many-body entangled quantum states studied in condensed matter physics can be primary resources for quantum information, allowing any quantum computation to be realized using measurements alone, on the state. Such a universal state would be…

Quantum Physics · Physics 2013-05-29 Xie Chen , Bei Zeng , Zhengcheng Gu , Beni Yoshida , Isaac L. Chuang

Characterizing the entanglement structure of ground states of local Hamiltonians is a fundamental problem in quantum information. In this work we study the computational complexity of this problem, given the Hamiltonian as input. Our main…

Quantum Physics · Physics 2024-11-08 Adam Bouland , Chenyi Zhang , Zixin Zhou

A key feature of ground states of gapped local 1D Hamiltonians is their relatively low entanglement --- they are well approximated by matrix product states (MPS) with bond dimension scaling polynomially in the length $N$ of the chain, while…

Quantum Physics · Physics 2019-09-25 Alexander M. Dalzell , Fernando G. S. L. Brandao

We study Hamiltonians which have Kitaev's toric code as a ground state, and show how to construct a Hamiltonian which shares the ground space of the toric code, but which has gapless excitations with a continuous spectrum in the…

We study an effective Hamiltonian for the standard $\nu=1/3$ fractional quantum Hall system in the thin cylinder regime. We give a complete description of its ground state space in terms of what we call Fragmented Matrix Product States,…

Mathematical Physics · Physics 2022-01-12 Bruno Nachtergaele , Simone Warzel , Amanda Young

We prove that every injective Matrix Product State is the unique ground state of a simple hopping theory. We start by studying the low energy spectrum of parent Hamiltonians of injective Matrix Product States in a particular long range and…

Quantum Physics · Physics 2015-11-23 Benoît Descamps

We study general entanglement properties of the excited states of the one dimensional translational invariant free fermions and coupled harmonic oscillators. In particular, using the integrals of motion, we prove that these Hamiltonians…

Strongly Correlated Electrons · Physics 2019-11-13 Arash Jafarizadeh , M. A. Rajabpour

The current theoretical framework for topological phases of matter is based on the thermodynamic limit of a system with geometrically local interactions. A natural question is to what extent the notion of a phase of matter remains…

Quantum Physics · Physics 2024-09-10 Ali Lavasani , Michael J. Gullans , Victor V. Albert , Maissam Barkeshli