@article{21340, abstract = {Equilibrium quantum systems are often described by a gas of weakly interacting normal modes. Bringing such systems far from equilibrium, however, can drastically enhance mode-to-mode interactions. Understanding the resulting liquid is a fundamental question for quantum statistical mechanics and a practical question for engineering driven quantum devices. To tackle this question, we probe the non-equilibrium kinetics of one-dimensional plasmons in a long chain of Josephson junctions. We introduce multimode spectroscopy to controllably study the departure from equilibrium, witnessing the evolution from pairwise coupling between plasma modes at weak driving to dramatic, high-order, cascaded couplings at strong driving. Scaling to many-mode drives, we stimulate interactions between hundreds of modes, resulting in near-continuum internal dynamics. Imaging the resulting non-equilibrium plasmon populations, we then resolve the nonlocal redistribution of energy in the response to a weak perturbation—an explicit verification of the emergence of a strongly interacting, non-equilibrium liquid of plasmons.}, author = {Bubis, Anton and Vigliotti, Lucia and Serbyn, Maksym and Higginbotham, Andrew P}, issn = {2375-2548}, journal = {Science Advances}, number = {7}, publisher = {American Association for the Advancement of Science}, title = {{Non-equilibrium plasmon liquid in a Josephson junction chain}}, doi = {10.1126/sciadv.ady7222}, volume = {12}, year = {2026}, } @article{21480, abstract = {We present and test a protocol to learn the matrix-product operator (MPO) representation of an experimentally prepared quantum state. The protocol takes as input classical shadows corresponding to local randomized measurements, and outputs the tensors of an MPO maximizing a suitably defined fidelity with the experimental state. The tensor optimization is carried out sequentially, similarly to the well-known density matrix renormalization group algorithm. Our approach is provably efficient under certain technical conditions expected to be met in short-range correlated states and in typical noisy experimental settings. Under the same conditions, we also provide an efficient scheme to estimate fidelities between the learned and the experimental states. We experimentally demonstrate our protocol by learning entangled quantum states of up to N = 96 qubits in a superconducting quantum processor. Our method upgrades classical shadows to large-scale quantum computation and simulation experiments.}, author = {Votto, Matteo and Ljubotina, Marko and Lancien, Cécilia and Cirac, J. Ignacio and Zoller, Peter and Serbyn, Maksym and Piroli, Lorenzo and Vermersch, Benoît}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {9}, publisher = {American Physical Society}, title = {{Learning mixed quantum states in large-scale experiments}}, doi = {10.1103/rbg2-f61m}, volume = {136}, year = {2026}, } @article{21501, abstract = {Kinetically constrained models were originally introduced to capture slow relaxation in glassy systems, where dynamics are hindered by local constraints instead of energy barriers. Their quantum counterparts have recently drawn attention for exhibiting highly degenerate eigenstates at zero energy—known as zero modes—stemming from chiral symmetry. Yet, the structure and implications of these zero modes remain poorly understood. In this work, we focus on the properties of the zero mode subspace in quantum kinetically constrained models with a U(1) particle-conservation symmetry. We use the U(1) East, which lacks inversion symmetry, and the inversion-symmetric U(1) East-West models to illustrate our two main results. First, we observe that the simultaneous presence of constraints and chiral symmetry generally leads to a parametric increase in the number of zero modes due to the fragmentation of the many-body Hilbert space into disconnected sectors. Second, we generalize the concept of compact localized states from single-particle physics and introduce the notion of collective bound states, a special kind of nonergodic eigenstates that are robust to enlarging the system size. We formulate sufficient criteria for their existence, arguing that the degenerate zero mode subspace plays a central role, and demonstrate bound states in both example models and in a two-dimensional model, the U(1) North-East, and in the pairflip model, a system without particle conservation. Our results motivate a systematic study of bound states and their relation to ergodicity breaking, transport, and other properties of quantum kinetically constrained models. }, author = {Nicolau Jimenez, Eulalia and Ljubotina, Marko and Serbyn, Maksym}, issn = {2691-3399}, journal = {PRX Quantum}, publisher = {American Physical Society}, title = {{Fragmentation, zero modes, and collective bound states in constrained models}}, doi = {10.1103/sl79-1xgb}, volume = {7}, year = {2026}, } @article{18710, abstract = {We present an ab initio theoretical method to calculate the resonant Auger spectrum in the presence of ultrafast dissociation. The method is demonstrated by deriving the L-VV resonant Auger spectrum mediated by the 2p3/2−1σ* resonance in HCl, where the electronic Auger decay and nuclear dissociation occur on the same time scale. The Auger decay rates are calculated within the one-center approximation and are shown to vary significantly with the inter-nuclear distance. A quantum-mechanical description of dissociation is effectuated by propagating the corresponding Franck–Condon factors. The calculated profiles of Auger spectral lines resemble those of atomic Auger decay but here the characteristic tails extend towards lower electron kinetic energies, which reflect specific features of the potential energy curves. The presented method can describe the resonant Auger spectrum for an arbitrary speed of dissociation and simplifies to known approximations in the limiting cases.}, author = {Hrast, Mateja and Ljubotina, Marko and Zitnik, Matjaz}, issn = {1463-9076}, journal = {Physical Chemistry Chemical Physics}, number = {3}, pages = {1473--1482}, publisher = {Royal Society of Chemistry}, title = {{Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl}}, doi = {10.1039/d4cp03727h}, volume = {27}, year = {2025}, } @misc{19791, abstract = {Confinement is a prominent phenomenon in condensed matter and high-energy physics that has recently become the focus of quantum-simulation experiments of lattice gauge theories (LGTs). As such, a theoretical understanding of the effect of confinement on LGT dynamics is not only of fundamental importance, but can lend itself to upcoming experiments. Here, we show how confinement in a Z2 LGT can be locally avoided by proximity to a resonance between the fermion mass and the electric field strength. Furthermore, we show that this local deconfinement can become global for certain initial conditions, where information transport occurs over the entire chain. In addition, we show how this can lead to strong quantum many-body scarring starting in different initial states. Our findings provide deeper insights into the nature of confinement in Z2 LGTs and can be tested on current and near-term quantum devices.}, author = {Desaules, Jean-Yves Marc}, keywords = {lattice gauge theories, quantum many-body scars, deconfinement}, publisher = {Institute of Science and Technology Austria}, title = {{Research Data for "Mass-Assisted Local Deconfinement in a Confined Z2 Lattice Gauge Theory"}}, doi = {10.15479/AT:ISTA:19791}, year = {2025}, } @article{19833, abstract = {Eigenstates of quantum many-body systems are often used to define phases of matter in and out of equilibrium; however, experimentally accessing highly excited eigenstates is a challenging task, calling for alternative strategies to dynamically probe nonequilibrium phases. In this work, we characterize the dynamical properties of a disordered spin chain, focusing on the spin-glass regime. Using tensor-network simulations, we observe oscillatory behavior of local expectation values and bipartite entanglement entropy. We explain these oscillations deep in the many-body localized spin-glass regime via a simple theoretical model. From perturbation theory, we predict the timescales up to which our analytical description is valid and confirm it with numerical simulations. Finally, we study the correlation length dynamics, which, after a long-time plateau, resume growing in line with renormalization group (RG) expectations. Our work suggests that RG predictions can be quantitatively tested against numerical simulations and experiments, potentially enabling microscopic descriptions of dynamical phases in large systems.}, author = {Brighi, Pietro and Ljubotina, Marko and Serbyn, Maksym}, issn = {2469-9969}, journal = {Physical Review B}, number = {22}, publisher = {American Physical Society}, title = {{Probing the many-body localized spin-glass phase through quench dynamics}}, doi = {10.1103/9fms-ygfz}, volume = {111}, year = {2025}, } @article{19852, abstract = {Technology involving hybrid superconductor–semiconductor materials is a promising avenue for engineering quantum devices for information storage, manipulation, and transmission. Proximity-induced superconducting correlations are an essential part of such devices. While the proximity effect in the conduction band of common semiconductors is well understood, its manifestation in confined hole gases, realized for instance in germanium, is an active area of research. Lower-dimensional hole-based systems, particularly in germanium, are emerging as an attractive platform for a variety of solid-state quantum devices, due to their combination of efficient spin and charge control and long coherence times. The recent experimental realization of the proximity effect in germanium thus calls for a theoretical description that is tailored to hole gases. In this work, we propose a simple model to describe proximity-induced superconductivity in two-dimensional hole gases, incorporating both the heavy-hole (HH) and light-hole (LH) bands. We start from the Luttinger–Kohn model, introduce three parameters that characterize hopping across the superconductor–semiconductor interface, and derive explicit intraband and interband effective pairing terms for the HH and LH bands. Unlike previous approaches, our theory provides a quantitative relationship between induced pairings and interface properties. Restricting our general model to an experimentally relevant case where only the HH band crosses the chemical potential, we predict the coexistence of 𝑠-wave and 𝑑-wave singlet pairings, along with triplet-type pairings, and modified Zeeman and Rashba spin–orbit couplings. Our results thus present a starting point for theoretical modeling of quantum devices based on proximitized hole gases, fueling further progress in quantum technology.}, author = {Babkin, Serafim and Joecker, Benjamin and Flensberg, Karsten and Serbyn, Maksym and Danon, Jeroen}, issn = {2469-9969}, journal = {Physical Review B}, number = {21}, publisher = {American Physical Society}, title = {{Superconducting proximity effect in two-dimensional hole gases}}, doi = {10.1103/k4jh-pnxy}, volume = {111}, year = {2025}, } @article{20327, abstract = {Confinement is a prominent phenomenon in condensed-matter and high-energy physics that has recently become the focus of quantum-simulation experiments of lattice gauge theories (LGTs). As such, a theoretical understanding of the effect of confinement on LGT dynamics is not only of fundamental importance but also can lend itself to upcoming experiments. Here we show how confinement in a Z2 LGT can be avoided by proximity to a resonance between the fermion mass and the electric field strength. Furthermore, we show that this local deconfinement can become global for certain initial conditions, where information transport occurs over the entire chain. In addition, we show how this can lead to strong quantum many-body scarring starting in different initial states. Our findings provide deeper insights into the nature of confinement in Z2 LGTs and can be tested on current and near-term quantum devices.}, author = {Desaules, Jean-Yves Marc and Iadecola, Thomas and Halimeh, Jad C.}, issn = {2469-9969}, journal = {Physical Review B}, number = {1}, publisher = {American Physical Society}, title = {{Mass-assisted local deconfinement in a confined Z2 lattice gauge theory}}, doi = {10.1103/mfg2-t6gb}, volume = {112}, year = {2025}, } @article{20503, abstract = {We introduce a class of interacting fermionic quantum models in d dimensions with nodal interactions that exhibit superdiffusive transport. We establish nonperturbatively that the nodal structure of the interactions gives rise to long-lived quasiparticle excitations that result in a diverging diffusion constant, even though the system is fully chaotic. Using a Boltzmann equation approach, we find that the charge mode acquires an anomalous dispersion relation at long wavelength ωðqÞ ∼ qz with dynamical exponent z ¼ min½ð2n þ dÞ=2n; 2, where n is the order of the nodal point in momentum space. We verify our predictions in one-dimensional systems using tensor-network techniques.}, author = {Wang, Yupeng and Ren, Jie and Gopalakrishnan, Sarang and Vasseur, Romain}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {16}, publisher = {American Physical Society}, title = {{Superdiffusive transport in chaotic quantum systems with nodal interactions}}, doi = {10.1103/xx9z-4j6c}, volume = {135}, year = {2025}, } @article{20646, abstract = {Describing general quantum many-body dynamics is a challenging task due to the exponential growth of the Hilbert space with system size. The time-dependent variational principle (TDVP) provides a powerful tool to tackle this task by projecting quantum evolution onto a classical dynamical system within a variational manifold. In classical systems, periodic orbits play a crucial role in understanding the structure of the phase space and the long-term behavior of the system. However, finding periodic orbits is generally difficult, and their existence and properties in generic TDVP dynamics over matrix product states have remained largely unexplored. In this work, we develop an algorithm to systematically identify and characterize periodic orbits in TDVP dynamics. Applying our method to the periodically kicked Ising model, we uncover both stable and unstable periodic orbits. We characterize the Kolmogorov-Arnold-Moser tori in the vicinity of stable periodic orbits and track the change of the periodic orbits as we modify the Hamiltonian parameters. We observe that periodic orbits exist at any value of the coupling constant of the kicked Ising model between prethermal and fully thermalizing regimes, but their relevance to quantum dynamics and imprint on quantum eigenstates diminishes as the system leaves the prethermal regime. Our results demonstrate that periodic orbits provide valuable insights into the TDVP approximation of quantum many-body evolution and establish a closer connection between quantum and classical chaos.}, author = {Petrova, Elena and Ljubotina, Marko and Yalniz, Gökhan and Serbyn, Maksym}, issn = {2691-3399}, journal = {PRX Quantum}, number = {4}, publisher = {American Physical Society}, title = {{Finding periodic orbits in projected quantum many-body dynamics}}, doi = {10.1103/tldp-kvkd}, volume = {6}, year = {2025}, } @article{20709, abstract = {Non-Hermitian many-body localization (NH MBL) has emerged as a possible scenario for stable localization in open systems, as suggested by spectral indicators identifying a putative transition for finite system sizes. In this work, we shift the focus to dynamical probes, specifically the steady-state spin current, to investigate transport properties in a disordered, non-Hermitian XXZ spin chain. Through exact diagonalization for small systems and tensor-network methods for larger chains, we demonstrate that the steady-state current remains finite and decays exponentially with disorder strength, showing no evidence of a transition up to disorder values far beyond the previously claimed critical point. Our results reveal a stark discrepancy between spectral indicators, which suggest localization, and transport behavior, which indicates delocalization. This highlights the importance of dynamical observables in characterizing NH MBL and suggests that traditional spectral measures may not fully capture the physics of non-Hermitian systems. Additionally, we observe a noncommutativity of limits in system size and time, further complicating the interpretation of finite-size studies. These findings challenge the existence of NH MBL in the studied model and underscore the need for alternative approaches to understanding localization in non-Hermitian settings.}, author = {Brighi, Pietro and Ljubotina, Marko and Roccati, Federico and Balducci, Federico}, issn = {2643-1564}, journal = {Physical Review Research}, number = {4}, publisher = {American Physical Society}, title = {{Finite steady-state current defies non-Hermitian many-body localization}}, doi = {10.1103/crwj-x7j8}, volume = {7}, year = {2025}, } @article{19012, abstract = {False vacuum decay—the transition from a metastable quantum state to a true vacuum state—plays an important role in quantum field theory and non-equilibrium phenomena such as phase transitions and dynamical metastability. The non-perturbative nature of false vacuum decay and the limited experimental access to this process make it challenging to study, leaving several open questions regarding how true vacuum bubbles form, move and interact. Here we observe quantized bubble formation in real time, a key feature of false vacuum decay dynamics, using a quantum annealer with 5,564 superconducting flux qubits. We develop an effective model that captures both initial bubble creation and subsequent interactions, and remains accurate under dissipation. The annealer reveals coherent scaling laws in the driven many-body dynamics for more than 1,000 intrinsic qubit time units. This work provides a method for investigating false vacuum dynamics of large quantum systems in quantum annealers.}, author = {Vodeb, Jaka and Desaules, Jean-Yves Marc and Hallam, Andrew and Rava, Andrea and Humar, Gregor and Willsch, Dennis and Jin, Fengping and Willsch, Madita and Michielsen, Kristel and Papić, Zlatko}, issn = {1745-2481}, journal = {Nature Physics}, pages = {386--392}, publisher = {Springer Nature}, title = {{Stirring the false vacuum via interacting quantized bubbles on a 5,564-qubit quantum annealer}}, doi = {10.1038/s41567-024-02765-w}, volume = {21}, year = {2025}, } @misc{19623, abstract = {Persistent revivals recently observed in Rydberg atom simulators have challenged our understanding of thermalization and attracted much interest to the concept of quantum many-body scars (QMBSs). QMBSs are non-thermal highly excited eigenstates that coexist with typical eigenstates in the spectrum of many-body Hamiltonians, and have since been reported in multiple theoretical models, including the so-called PXP model, approximately realized by Rydberg simulators. At the same time, questions of how common QMBSs are and in what models they are physically realized remain open. In this Letter, we demonstrate that QMBSs exist in a broader family of models that includes and generalizes PXP to longer-range constraints and states with different periodicity. We show that in each model, multiple QMBS families can be found. Each of them relies on a different approximate 𝔰𝔲⁡(2) algebra, leading to oscillatory dynamics in all cases. However, in contrast to the PXP model, their observation requires launching dynamics from weakly entangled initial states rather than from a product state. QMBSs reported here may be experimentally probed using Rydberg atom simulator in the regime of longer-range Rydberg blockades.}, author = {Desaules, Jean-Yves Marc}, keywords = {quantum many-body scars, non-equilibrium physics, Rydberg atoms}, publisher = {Institute of Science and Technology Austria}, title = {{Research Data for "Quantum Many-Body Scars beyond the PXP Model in Rydberg Simulators"}}, doi = {10.15479/AT:ISTA:19623}, year = {2025}, } @article{19664, abstract = {Persistent revivals recently observed in Rydberg atom simulators have challenged our understanding of thermalization and attracted much interest to the concept of quantum many-body scars (QMBSs). QMBSs are non-thermal highly excited eigenstates that coexist with typical eigenstates in the spectrum of many-body Hamiltonians, and have since been reported in multiple theoretical models, including the so-called PXP model, approximately realized by Rydberg simulators. At the same time, questions of how common QMBSs are and in what models they are physically realized remain open. In this Letter, we demonstrate that QMBSs exist in a broader family of models that includes and generalizes PXP to longer-range constraints and states with different periodicity. We show that in each model, multiple QMBS families can be found. Each of them relies on a different approximate algebra, leading to oscillatory dynamics in all cases. However, in contrast to the PXP model, their observation requires launching dynamics from weakly entangled initial states rather than from a product state. QMBSs reported here may be experimentally probed using Rydberg atom simulator in the regime of longer-range Rydberg blockades.}, author = {Kerschbaumer, Aron and Ljubotina, Marko and Serbyn, Maksym and Desaules, Jean-Yves Marc}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {16}, publisher = {American Physical Society}, title = {{Quantum many-body scars beyond the PXP model in Rydberg simulators}}, doi = {10.1103/PhysRevLett.134.160401}, volume = {134}, year = {2025}, } @inproceedings{21272, abstract = {Finding the ground state of Ising spin glasses is notoriously difficult due to disorder and frustration. Often, this challenge is framed as a combinatorial optimization problem, for which a common strategy employs simulated annealing, a Monte Carlo (MC)-based algorithm that updates spins one at a time. Yet, these localized updates can cause the system to become trapped in local minima. Cluster algorithms (CAs) were developed to address this limitation and have demonstrated considerable success in studying ferromagnetic systems; however, they tend to encounter percolation issues when applied to generic spin glasses. In this work, we introduce a novel CA designed to tackle these challenges by leveraging precomputed two-point correlations, aiming solve combinatorial optimization problems in the form of Max-Cut more efficiently. In our approach, clusters are formed probabilistically based on these correlations. Various classical and quantum algorithms can be employed to generate correlations that embody information about the energy landscape of the problem. By utilizing this information, the algorithm aims to identify groups of spins whose simultaneous flipping induces large transitions in configuration space with high acceptance probability - even at low energy levels - thereby escaping local minima more effectively. Notably, clusters generated using correlations from the Quantum Approximate Optimization Algorithm exhibit high acceptance rates at low temperatures. These acceptance rates often increase with circuit depth, accelerating the algorithm and enabling more efficient exploration of the solution space.}, author = {Eder, Peter J. and Kerschbaumer, Aron and Finžgar, Jernej Rudi and Medina Ramos, Raimel A and Schuetz, Martin J. A. and Katzgraber, Helmut G. and Braun, Sarah and Mendl, Christian B.}, booktitle = {2025 IEEE International Conference on Quantum Computing and Engineering}, location = {Albuquerque, NM, United States}, publisher = {IEEE}, title = {{Quantum-guided cluster algorithms for combinatorial optimization}}, doi = {10.1109/qce65121.2025.00033}, year = {2025}, } @article{18110, abstract = {We study a chaotic particle-conserving kinetically constrained model, with a single parameter which allows us to break reflection symmetry. Through extensive numerical simulations we find that the domain wall state shows a variety of dynamical behaviors from localization all the way to ballistic transport, depending on the value of the reflection breaking parameter. Surprisingly, such anomalous behavior is not mirrored in infinite-temperature dynamics, which appear to scale diffusively, in line with expectations for generic interacting models. However, studying the particle density gradient, we show that the lack of reflection symmetry affects infinite-temperature dynamics, resulting in an asymmetric dynamical structure factor. This is in disagreement with normal diffusion and suggests that the model may also exhibit anomalous dynamics at infinite temperature in the thermodynamic limit. Finally, we observe low-entangled eigenstates in the spectrum of the model, a telltale sign of quantum many-body scars.}, author = {Brighi, Pietro and Ljubotina, Marko}, issn = {2469-9969}, journal = {Physical Review B}, number = {10}, publisher = {American Physical Society}, title = {{Anomalous transport in the kinetically constrained quantum East-West model}}, doi = {10.1103/PhysRevB.110.L100304}, volume = {110}, year = {2024}, } @article{18176, abstract = {Introducing a class of SU(2) invariant quantum unitary circuits generating chiral transport, we examine the role of broken space-reflection and time-reversal symmetries on spin-transport properties. Upon adjusting parameters of local unitary gates, the dynamics can be either chaotic or integrable. The latter corresponds to a generalization of the space-time discretized (Trotterized) higher-spin quantum Heisenberg chain. We demonstrate that breaking of space-reflection symmetry results in a drift in the dynamical spin susceptibility. Remarkably, we find a universal drift velocity given by a simple formula, which, at zero average magnetization, depends only on the values of SU(2) Casimir invariants associated with local spins. In the integrable case, the drift velocity formula is confirmed analytically based on the exact solution of thermodynamic Bethe ansatz equations. Finally, by inspecting the large fluctuations of the time-integrated current between two halves of the system in stationary maximum-entropy states, we demonstrate violation of the Gallavotti-Cohen symmetry, implying that such states cannot be regarded as equilibrium ones. We show that the scaled cumulant generating function of the time-integrated current instead obeys a generalized fluctuation relation.}, author = {Zadnik, Lenart and Ljubotina, Marko and Krajnik, Žiga and Ilievski, Enej and Prosen, Tomaž}, issn = {2691-3399}, journal = {PRX Quantum}, number = {3}, publisher = {American Physical Society}, title = {{Quantum many-body spin ratchets}}, doi = {10.1103/PRXQuantum.5.030356}, volume = {5}, year = {2024}, } @article{18488, abstract = {The advancement of quantum simulators motivates the development of a theoretical framework to assist with efficient state preparation in quantum many-body systems. Generally, preparing a target entangled state via unitary evolution with time-dependent couplings is a challenging task and very little is known about the existence of solutions and their properties. In this work we develop a constructive approach for preparing matrix product states (MPS) via continuous unitary evolution. We provide an explicit construction of the operator that exactly implements the evolution of a given MPS along a specified direction in its tangent space. This operator can be written as a sum of local terms of finite range, yet it is in general non-Hermitian. Relying on the explicit construction of the non-Hermitian generator of the dynamics, we demonstrate the existence of a Hermitian sequence of operators that implements the desired MPS evolution with an error that decreases exponentially with the operator range. The construction is benchmarked on an explicit periodic trajectory in a translationally invariant MPS manifold. We demonstrate that the Floquet unitary generating the dynamics over one period of the trajectory features an approximate MPS-like eigenstate embedded among a sea of thermalizing eigenstates. These results show that our construction is not only useful for state preparation and control of many-body systems, but also provides a generic route towards Floquet scars—periodically driven models with quasilocal generators of dynamics that have exact MPS eigenstates in their spectrum.}, author = {Ljubotina, Marko and Petrova, Elena and Schuch, Norbert and Serbyn, Maksym}, issn = {2691-3399}, journal = {PRX Quantum}, number = {4}, publisher = {American Physical Society}, title = {{Tangent space generators of matrix product states and exact floquet quantum scars}}, doi = {10.1103/prxquantum.5.040311}, volume = {5}, year = {2024}, } @article{18616, abstract = {By patterning an ultrathin layered structure with tiny wells, physicists have created and imaged peculiar states known as quantum scars — revealing behaviour that could be used to boost the performance of electronic devices.}, author = {Abanin, Dmitry and Serbyn, Maksym}, issn = {1476-4687}, journal = {Nature}, number = {8040}, pages = {825--826}, publisher = {Springer Nature}, title = {{Quantum scars make their mark in graphene}}, doi = {10.1038/d41586-024-03649-y}, volume = {635}, year = {2024}, } @article{18627, abstract = {In contrast with extended Bloch waves, a single particle can become spatially localized due to the so-called skin effect originating from non-Hermitian pumping. Here we show that in kinetically constrained many-body systems, the skin effect can instead manifest as dynamical amplification within the Fock space, beyond the intuitively expected and previously studied particle localization and clustering. We exemplify this non-Hermitian Fock skin effect in an asymmetric version of the PXP model and show that it gives rise to ergodicity-breaking eigenstates—the non-Hermitian analogs of quantum many-body scars. A distinguishing feature of these non-Hermitian scars is their enhanced robustness against external disorders. We propose an experimental realization of the non-Hermitian scar enhancement in a tilted Bose-Hubbard optical lattice with laser-induced loss. Additionally, we implement digital simulations of such scar enhancement on the IBM quantum processor. Our results show that the Fock skin effect provides a powerful tool for creating robust nonergodic states in generic open quantum systems.}, author = {Shen, Ruizhe and Qin, Fang and Desaules, Jean-Yves Marc and Papić, Zlatko and Lee, Ching Hua}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {21}, publisher = {American Physical Society}, title = {{Enhanced many-body quantum scars from the non-hermitian fock skin effect}}, doi = {10.1103/PhysRevLett.133.216601}, volume = {133}, year = {2024}, }