papers

Publications (63)

quant-ph2012

Radiation matter entanglement

Israel Klich

The quantization of the electromagnetic field in the presence of material bodies, at zero temperature is considered. It is shown that a dielectric does not act as thermal bath for…

cond-mat.mes-hall2014

Fluctuations and Entanglement spectrum in quantum Hall states

Alexandru Petrescu, H. Francis Song, Stephan Rachel +6

The measurement of quantum entanglement in many-body systems remains challenging. One experimentally relevant fact about quantum entanglement is that in systems whose degrees of fr…

cond-mat.dis-nn2013

A non-perturbative expression for the transmission through a leaky chiral edge mode

Kun W. Kim, Israel Klich, Gil Refael

Chiral edge modes of topological insulators and Hall states exhibit non-trivial behavior of conductance in the presence of impurities or additional channels. We will present a simp…

quant-ph2008

Casimir forces in a T operator approach

Oded Kenneth, Israel Klich

We explore the scattering approach to Casimir forces. Our main tool is the description of Casimir energy in terms of transition operators, as presented in Kenneth and Klich, Phys.…

cond-mat.stat-mech2017

Entropy, gap and a multi-parameter deformation of the Fredkin spin chain

Zhao Zhang, Israel Klich

We introduce a multi-parameter deformation of the Fredkin spin chain whose ground state is a weighted superposition of Dyck paths, depending on a set of parameters alon…

cond-mat.mes-hall2010

Entanglement from Charge Statistics: Exact Relations for Many-Body Systems

H. Francis Song, Christian Flindt, Stephan Rachel +2

We present exact formulas for the entanglement and Rényi entropies generated at a quantum point contact (QPC) in terms of the statistics of charge fluctuations, which we illustrat…

quant-ph2006

Entanglement entropy of fermions in any dimension and the Widom conjecture

Dimitri Gioev, Israel Klich

We show that entanglement entropy of free fermions scales faster then area law, as opposed to the scaling for the harmonic lattice, for example. We also suggest and provi…

cond-mat.dis-nn2023

Measurement Induced Chirality II: Diffusion and Disorder

Brian J J Khor, Matthew Wampler, Gil Refael +1

Repeated quantum measurements can generate effective new non-equilibrium dynamics in matter. Here we combine such a measurement driven system with disorder. In particular, we inves…

quant-ph2019

Spatiotemporal graph states from a single optical parametric oscillator

Rongguo Yang, Jing Zhang, Israel Klich +2

An experimental scheme is proposed for building massively multipartite entangled states using both the spatial and the frequency modes of an optical parametric oscillator. We provi…

quant-ph2004

Lower entropy bounds and particle number fluctuations in a Fermi sea

Israel Klich

We demonstrate, in an elementary manner, that given a partition of the single particle Hilbert space into orthogonal subspaces, a Fermi sea may be factored into pairs of entangled…

cond-mat.str-el2014

Probing Competing and Intertwined Orders with Resonant Inelastic x-ray Scattering in the Hole-Doped Cuprates

David Benjamin, Israel Klich, Eugene Demler

We develop a formalism to study indirect resonant inelastic x-ray scattering (RIXS) in systems with itinerant electrons, accounting for the attraction between valence electrons and…

cond-mat.stat-mech2013

Hermitian and non-Hermitian thermal Hamiltonians

Adrian E. Feiguin, Israel Klich

Thermal density matrices can be described by a pure quantum state within the thermofield formalism. Here we show how to construct a class of Hamiltonians realizing a thermofield st…

cond-mat.supr-con2011

Birman-Schwinger and the number of Andreev states in BCS superconductors

Israel Klich

The number of bound states due to inhomogeneities in a BCS superconductor is usually established either by variational means or via exact solutions of particularly simple, symmetri…

math-ph2007

Fredholm determinants and the statistics of charge transport

Joseph E. Avron, Sven Bachmann, Gian Michele Graf +1

Using operator algebraic methods we show that the moment generating function of charge transport in a system with infinitely many non-interacting Fermions is given by a determinant…

quant-ph2019

Closed hierarchies and non-equilibirum steady states of driven systems

Israel Klich

We present a class of tractable non-equilibrium dynamical quantum systems which includes combinations of injection, detection and extraction of particles interspersed by unitary ev…

cond-mat.dis-nn2017

Aging, memory, and nonhierarchical energy landscape of spin jam

Anjana Samarakoon, Taku J. Sato, Tianran Chen +5

The notion of complex energy landscape underpins the intriguing dynamical behaviors in many complex systems ranging from polymers, to brain activity, to social networks and glass t…

quant-ph2008

Quantum Noise as an Entanglement Meter

Israel Klich, Leonid Levitov

Entanglement entropy, which is a measure of quantum correlations between separate parts of a many-body system, has emerged recently as a fundamental quantity in broad areas of theo…

quant-ph2010

Lieb-Robinson bounds for commutator-bounded operators

Isabeau Prémont-Schwarz, Alioscia Hamma, Israel Klich +1

We generalize the Lieb-Robinson theorem to systems whose Hamiltonian is the sum of local operators whose commutators are bounded.

cond-mat.mtrl-sci2025

Quantum-Annealing Enhanced Machine Learning for Interpretable Phase Classification of High-Entropy Alloys

Diego Ibarra Hoyos, Gia-Wei Chern, Israel Klich +1

High entropy alloys (HEAs) offer unprecedented compositional flexibility for designing advanced materials, yet predicting their crystallographic phases remains a key bottleneck due…

hep-th2000

Photon Green's function and the Casimir energy in a medium

Israel Klich

A new expansion is established for the Green's function of the electromagnetic field in a medium with arbitrary and . The obtained Born series are shown to consist of two…

cond-mat.stat-mech2017

Entanglement Hamiltonians and entropy in 1+1D chiral fermion systems

Israel Klich, Diana Vaman, Gabriel Wong

In past work we introduced a method which allows for exact computations of entanglement Hamiltonians. The method relies on computing the resolvent for the projected (on the entangl…

quant-ph2006

Opposites Attract - A Theorem About The Casimir Force

Oded Kenneth, Israel Klich

We consider the Casimir interaction between (non-magnetic) dielectric bodies or conductors. Our main result is a proof that the Casimir force between two bodies related by reflecti…

cond-mat.str-el2017

Auxiliary fermion approach to the RIXS spectrum in a doped cuprate

Yifei Shi, Andrew James, Eugene Demler +1

We describe a method for calculating the resonant inelastic X-ray scattering (RIXS) response---including the dynamics of the transient core hole---of many-body systems with non-tri…

cond-mat.supr-con2007

Effect of inhomogeneous coupling on superconductivity

Yue Zou, Israel Klich, Gil Refael

We investigate the influence of inhomogeneity in the pairing coupling constant on dirty BCS superconductors, focusing on , the order parameter , and th…

cond-mat.mtrl-sci2021

Freezing of a disorder induced quantum spin liquid

Xiao Hu, Daniel M. Pajerowski, Depei Zhang +8

is a square-lattice magnet with super-exchange between S=1/2 spins mediated by randomly distributed Te and W ions. Here, using sub-K…

cond-mat.stat-mech2016

Deformed Fredkin Spin Chain with Extensive Entanglement

Olof Salberger, Takuma Udagawa, Zhao Zhang +3

We introduce a new spin chain which is a deformation of the Fredkin spin chain and has a phase transition between bounded and extensive entanglement entropy scaling. In this chain,…

cond-mat.stat-mech2012

Full counting statistics and the Edgeworth series for matrix product states

Yifei Shi, Israel Klich

We consider full counting statistics of spin in matrix product states. In particular, we study the approach to gaussian distribution for magnetization. We derive the asymptotic cor…

quant-ph2012

On the entanglement of a quantum field with a dispersive medium

Israel Klich

In this Letter we study the entanglement of a quantum radiation field interacting with a dielectric medium. In particular, we describe the quantum mixed state of a field interactin…

hep-th2021

Emergent geometry and path integral optimization for a Lifshitz action

Amr Ahmadain, Israel Klich

Extending the background metric optimization procedure for Euclidean path integrals of two-dimensional conformal field theories, introduced by Caputa et al. (Phys. Rev. Lett. 119,…

hep-th2013

Entanglement Temperature and Entanglement Entropy of Excited States

Gabriel Wong, Israel Klich, Leopoldo A. Pando Zayas +1

We derive a general relation between the ground state entanglement Hamiltonian and the physical stress tensor within the path integral formalism. For spherical entangling surfaces…

cond-mat.mtrl-sci2016

Resonant inelastic x-ray scattering as a probe of band structure effects in cuprates

Márton Kanász-Nagy, Yifei Shi, Israel Klich +1

We analyze within quasi-particle theory a recent resonant inelastic x-ray scattering (RIXS) experiment on with the incoming photon energy detuned at sev…

cond-mat.str-el2011

Edge modes in band topological insulators

Lukasz Fidkowski, T. S. Jackson, Israel Klich

We characterize gapless edge modes in translation invariant topological insulators. We show that the edge mode spectrum is a continuous deformation of the spectrum of a certain glu…

math-ph2019

Solution of the Metropolis dynamics on a complete graph with application to the Markov chain Mpemba effect

Israel Klich, Marija Vucelja

We find analytically the complete set of eigenvalues and eigenvectors associated with Metropolis dynamics on a complete graph. As an application, we use this information to study a…

math-ph2026

On Factorizing Aggregate Counting Distributions into Independent Latent Processes

Israel Klich

The paper develops a mathematical framework for decomposing the distribution of an aggregate counting variable into independent latent counting processes by studying positive facto…

#positive factorization#latent counting processes#entropy optimization#generating functions
quant-ph2022

Stirring by Staring: Measurement Induced Chirality

Matthew Wampler, Brian J. J. Khor, Gil Refael +1

In quantum mechanics, the observer necessarily plays an active role in the dynamics of the system, making it difficult to probe a system without disturbing it. Here, we leverage th…

quant-ph2022

Arrested Development and Fragmentation in Strongly-Interacting Floquet Systems

Matthew Wampler, Israel Klich

We explore how interactions can facilitate classical like dynamics in models with sequentially activated hopping. Specifically, we add local and short range interaction terms to th…

cond-mat.mes-hall2014

A note on the Full Counting Statistics of paired fermions

Israel Klich

We study the trace of the exponentials of general fermion bi-linears, including pairing terms, and including non Hermitian forms. In particular, we give elementary derivations for…

cond-mat.stat-mech2024

Random walk with horizontal and cyclic currents

Joanna Li, Matthew Gerry, Israel Klich +1

We construct a minimal two-chain random walk model and study the information that fluctuations of the flux and higher cumulants can reveal about the model: its structure, parameter…

cond-mat.stat-mech2006

Towards measuring Entanglement Entropies in Many Body Systems

Israel Klich, Gil Refael, Alessandro Silva

We explore the relation between entanglement entropy of quantum many body systems and the distribution of corresponding, properly selected, observables. Such a relation is necessar…

cond-mat.stat-mech2022

Fragmentation and Novel Prethermal Dynamical Phases in Disordered, Strongly-Interacting Floquet Systems

Matthew Wampler, Israel Klich

We explore how disorder and interactions conspire in lattice models with sequentially activated hopping to produce novel k-body (or many-body) localized phases. Specifically, we sh…

cond-mat.other2009

Dispersion interaction between crossed conducting wires

John F. Dobson, Timothy Gould, Israel Klich

We compute the Van der Waals (nonretarded Casimir) interaction energy between two infinitely long, crossed conducting wires separated by a minimum distance much grea…

quant-ph2023

Coupled Fredkin and Motzkin chains from quantum six- and nineteen-vertex models

Zhao Zhang, Israel Klich

We generalize the area-law violating models of Fredkin and Motzkin spin chains into two dimensions by building quantum six- and nineteen-vertex models with correlated interactions.…

cond-mat.quant-gas2021

Quantum wakes in lattice fermions

Matthew Wampler, Peter Schauss, Eugene B Kolomeisky +1

The wake following a vessel in water is a signature interference effect of moving bodies, and, as described by Lord Kelvin, is contained within a constant universal angle. However,…

quant-ph2016

Quantum phase transition from bounded to extensive entanglement entropy in a frustration-free spin chain

Zhao Zhang, Amr Ahmadain, Israel Klich

We introduce a continuous family of frustration-free Hamiltonians with exactly solvable ground states. We prove that the {ground state of our model is non-degenerate and exhibits}…

cond-mat.mtrl-sci2025

From Quantum Annealing to Alloy Discovery: Towards Accelerated Design of High-Entropy Alloys

Diego Ibarra-Hoyos, Peter Connors, Ho Jang +6

Data scarcity remains a central challenge in materials discovery, where finding meaningful descriptors and tuning models for generalization is critical but inherently a discrete op…

cond-mat.str-el2015

Spin Jam: a quantum-fluctuation-induced glassy state of a frustrated magnet

Junjie Yang, Anjana Samarakoon, Sachith Dissanayake +8

Since the discovery of spin glasses in dilute magnetic systems, their study has been largely focused on understanding randomness and defects as the driving mechanism. The same para…

quant-ph2009

On the stability of topological phases on a lattice

Israel Klich

We study the stability of anyonic models on lattices to perturbations. We establish a cluster expansion for the energy of the perturbed models and use it to study the stability of…

cond-mat.mes-hall2011

Bipartite Fluctuations as a Probe of Many-Body Entanglement

H. Francis Song, Stephan Rachel, Christian Flindt +3

We investigate in detail the behavior of the bipartite fluctuations of particle number and spin in many-body quantum systems, focusing on systems where such U…

quant-ph2024

SWAP and Transpose by displacements, Stabilizer Renyi entropies for continuous variables and qudits and other applications

Israel Klich

In this note, I highlight a useful formula for the SWAP operator as an average of anti-correlated Heisenberg-Weyl displacements, valid for arbitrary-dimensional quantum systems. As…

quant-ph2018

Holographic rainbow networks for colorful Motzkin and Fredkin spin chains

Rafael N. Alexander, Amr Ahmadain, Zhao Zhang +1

We present bulk tensor networks that exactly represent the ground states of a continuous family of one-dimensional frustration-free Hamiltonians. These states, which are known as a…

cond-mat.stat-mech2018

The Mpemba index and anomalous relaxation

Israel Klich, Oren Raz, Ori Hirschberg +1

The Mpemba effect is a counter-intuitive relaxation phenomenon, where a system prepared at a hot temperature cools down faster than an identical system initiated at a cold temperat…

cond-mat.supr-con2016

Superconducting pairing in resonant inelastic X-ray scattering

Yifei Shi, David Benjamin, Eugene Demler +1

We develop a method to study the effect of the superconducting transition on resonant inelastic X-ray scattering (RIXS) signal in superconductors with an order parameter with an ar…

quant-ph2008

Novel Mechanisms for repulsive Casimir forces

Oded Kenneth, Israel Klich

We present two novel models for repulsive Casimir interaction between positive perturbations. One example relies on non locality of the dielectric response and one relies on interf…

quant-ph2024

Confinement and Kink Entanglement Asymmetry on a Quantum Ising Chain

Brian J. J. Khor, D. M. Kürkçüoglu, T. J. Hobbs +2

In this work, we explore the interplay of confinement, string breaking and entanglement asymmetry on a 1D quantum Ising chain. We consider the evolution of an initial domain wall a…

cs.LG2026

Perturbative Contrastive Physical Learning

Kyungeun Kim, Amanuel Anteneh, Israel Klich +2

Responses to perturbations are key to understanding physical systems. The ability to contrast such responses by comparing how a system reacts under slightly different conditions pr…

physics.optics2026

Laser interferometry as a robust neuromorphic platform for machine learning

Amanuel Anteneh, Kyungeun Kim, J. M. Schwarz +2

We present a method for implementing an optical neural network using only linear optical resources, namely field displacement and interferometry applied to coherent states of light…

cond-mat.mes-hall2009

Many-Body Entanglement: a New Application of the Full Counting Statistics

Israel Klich, Leonid Levitov

Entanglement entropy is a measure of quantum correlations between separate parts of a many-body system, which plays an important role in many areas of physics. Here we review recen…

cond-mat.stat-mech2016

Entanglement Hamiltonians for chiral fermions with zero modes

Israel Klich, Diana Vaman, Gabriel Wong

In this Letter we study the effect of topological zero modes on entanglement Hamiltonians and entropy of free chiral fermion systems in (1+1)d. We show how Riemann-Hilbert solution…

cond-mat.supr-con2013

Quasiparticle Theory of Resonant Inelastic X-ray Scattering in high-T cuprates

David Benjamin, Israel Klich, Eugene Demler

We develop a formalism for calculating resonant inelastic x-ray scattering (RIXS) spectra in systems of itinerant electrons with arbitrary band structures, accounting for the effec…

quant-ph2021

Exact holographic tensor networks for the Motzkin spin chain

Rafael N. Alexander, Glen Evenbly, Israel Klich

The study of low-dimensional quantum systems has proven to be a particularly fertile field for discovering novel types of quantum matter. When studied numerically, low-energy state…

cond-mat.stat-mech2024

Entanglement asymmetry and quantum Mpemba effect in the XY spin chain

Sara Murciano, Filiberto Ares, Israel Klich +1

Entanglement asymmetry is a quantity recently introduced to measure how much a symmetry is broken in a part of an extended quantum system. It has been employed to analyze the non-e…

quant-ph2024

Quantum lozenge tiling and entanglement phase transition

Zhao Zhang, Israel Klich

While volume violation of area law has been exhibited in several quantum spin chains, the construction of a corresponding ground state in higher dimensions, entangled in more than…

hep-th1999

Regularized Casimir energy for an infinite dielectric cylinder subject to light-velocity conservation

Israel Klich, August Romeo

The Casimir energy of a dilute dielectric cylinder, with the same light-velocity as in its surrounding medium, is evaluated exactly to first order in and numerically to high…