Measurement-altered Ising quantum criticality

Abstract

Quantum critical systems constitute appealing platforms for the exploration of novel measurement-induced phenomena due to their innate sensitivity to perturbations. We study the impact of measurement on paradigmatic Ising quantum critical chains using an explicit protocol, whereby correlated ancilla are entangled with the critical chain and then projectively measured. Using a perturbative analytic framework supported by extensive numerical simulations, we demonstrate that measurements can qualitatively alter long-distance correlations in a manner dependent on the choice of entangling gate, ancilla measurement basis, measurement outcome, and nature of ancilla correlations. We derive numerous quantitative predictions for the behavior of correlations in select measurement outcomes, and also identify two strategies for detecting measurement-altered Ising criticality in measurement-averaged quantities. First, averaging the square of the order-parameter expectation value over measurement outcomes retains memory of order parameter condensation germinated in fixed measurement outcomes -- even though on average the order parameter itself vanishes. Second, we show that, in certain cases, observables can be averaged separately over measurement outcomes residing in distinct symmetry sectors, and that these `symmetry-resolved averages' reveal measurement effects even when considering standard linearly averaged observables. We identify complementary regimes in which symmetry-resolved averages and post-selection can be pursued reasonably efficiently in experiment, with the former generically outperforming the latter in the limit of sufficiently weak ancilla-critical chain entanglement. Our framework naturally adapts to more exotic quantum critical points and highlights opportunities for potential experimental realization in NISQ hardware and in Rydberg arrays.

arXiv comment33 pages, 22 figures, comments added, new section and appendix

References in corpus (55)

• Measurement-Induced Phase Transitions in the Dynamics of Entanglement
• Quantum Zeno Effect and the Many-body Entanglement Transition
• Measurement-driven entanglement transition in hybrid quantum circuits
• Theory of the phase transition in random unitary circuits with measurements
• Measurement-induced criticality in random quantum circuits
• Unitary-projective entanglement dynamics
• Quantum Error Correction in Scrambling Dynamics and Measurement-Induced Phase Transition
• Efficient numerical simulations with Tensor Networks: Tensor Network Python (TeNPy)
• Dynamical purification phase transitions induced by quantum measurements
• Entanglement transition in a monitored free fermion chain -- from extended criticality to area law
• Entanglement in a fermion chain under continuous monitoring
• Scalable probes of measurement-induced criticality
• Measurement-Induced Entanglement Transitions in the Quantum Ising Chain: From Infinite to Zero Clicks
• Observation of measurement-induced quantum phases in a trapped-ion quantum computer
• Entanglement entropy for the long range Ising chain
• Competing density-wave orders in a one-dimensional hard-boson model
• Entanglement phase transitions in measurement-only dynamics
• Measurement-induced topological entanglement transitions in symmetric random quantum circuits
• Measurement Protected Quantum Phases
• Postselection-free entanglement dynamics via spacetime duality
• Self-Organized Error Correction in Random Unitary Circuits with Measurement
• Measurement-induced criticality in (2+1)-d hybrid quantum circuits
• Experimental Realization of a Measurement-Induced Entanglement Phase Transition on a Superconducting Quantum Processor
• Measurement-induced dark state phase transitions in long-ranged fermion systems
• Entanglement Transitions from Stochastic Resetting of Non-Hermitian Quasiparticles
• Long-range Ising and Kitaev Models: Phases, Correlations and Edge Modes
• Quantum criticality under decoherence or weak measurement
• Conformal invariance and quantum non-locality in critical hybrid circuits
• Symmetry enriched phases of quantum circuits
• Dissipative Floquet Dynamics: from Steady State to Measurement Induced Criticality in Trapped-ion Chains
• Measurement as a shortcut to long-range entangled quantum matter
• Growth of entanglement entropy under local projective measurements
• Fractal, logarithmic and volume-law entangled non-thermal steady states via spacetime duality
• Hierarchy of topological order from finite-depth unitaries, measurement and feedforward
• Quantum Circuits assisted by LOCC: Transformations and Phases of Matter
• Many-Body Quantum Zeno Effect and Measurement-Induced Subradiance Transition
• Spacetime duality between localization transitions and measurement-induced transitions
• Measurement-induced dynamics of many-body systems at quantum criticality
• Fermionic Gaussian states: an introduction to numerical approaches
• Measurements conspire nonlocally to restructure critical quantum states
• Cross Entropy Benchmark for Measurement-Induced Phase Transitions
• Entanglement entropy scaling transition under competing monitoring protocols
• Measurement-induced criticality as a data-structure transition
• Full counting statistics as probe of measurement-induced transitions in the quantum Ising chain
• Measurement-induced purification in large-N hybrid Brownian circuits
• Entanglement in one-dimensional critical state after measurements
• Probing sign structure using measurement-induced entanglement
• Channeling quantum criticality
• Nonlocality and entanglement in measured critical quantum Ising chains
• Microscopic characterization of Ising conformal field theory in Rydberg chains
• Diagnosing entanglement dynamics in noisy and disordered spin chains via the measurement-induced steady-state entanglement transition
• Neural-Network Decoders for Measurement Induced Phase Transitions
• Spontaneous symmetry breaking induced by quantum monitoring
• 2D Ising Model with a Defect Line
• Spin correlation function in 2D statistical mechanics models with inhomogeneous line defects

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• Stabilizer Rényi Entropy Encodes Fusion Rules of Topological Defects and Boundaries
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• Relaxation Critical Dynamics in Measurement-induced Phase Transitions
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• Exact solution to a Bhatnagar-Gross-Krook-type equation for quantum lattice gases with dephasing noise
• Homomorphism, substructure, and ideal: Elementary but rigorous aspects of renormalization group or hierarchical structure of topological orders
• Measurement-Induced Entanglement in Conformal Field Theory
• Asymptotic freedom, lost: Complex conformal field theory in the two-dimensional $O(N>2)$ nonlinear sigma model and its realization in Heisenberg spin chains
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