# Measurements conspire nonlocally to restructure critical quantum states

@inproceedings{Garratt2022MeasurementsCN, title={Measurements conspire nonlocally to restructure critical quantum states}, author={Samuel J. Garratt and Zack Weinstein and Ehud Altman}, year={2022} }

We study theoretically how local measurements perfomed on critical quantum ground states aﬀect long-distance correlations. These states are highly entangled and feature algebraic correlations between local observables. As a consequence, local measurements can have highly nonlocal eﬀects. Our focus is on Tomonaga-Luttinger liquid (TLL) ground states, a continuous family of critical states in one dimension whose structure is parameterized by a Luttinger parameter K . We show that arbitrarily weak…

## 5 Citations

### Measurement-induced phase transitions on dynamical quantum trees

- Physics
- 2022

Monitored many-body systems fall broadly into two dynamical phases, “entangling” or “disentangling”, separated by a transition as a function of the rate at which measurements are made on the system.…

### Nishimori's cat: stable long-range entanglement from finite-depth unitaries and weak measurements

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In the ﬁeld of monitored quantum circuits, it has remained an open question whether ﬁnite-time protocols for preparing long-range entangled (LRE) states lead to phases of matter which are stable to…

### Charge fluctuation and charge-resolved entanglement in monitored quantum circuit with $U(1)$ symmetry

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We study a (1+1)-dimensional quantum circuit consisting of Haar-random unitary gates and projective measurements, both of which conserve a total U (1) charge and thus have U (1) symmetry. In addition…

### Measurements on an Anderson Chain

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- 2022

We study the dynamics of a monitored single particle in a one-dimensional, Anderson-localized system. The time evolution is governed by Hamiltonian dynamics for ﬁxed time intervals, interrupted by…

### Entanglement and Absorbing-State Transitions in Interactive Quantum Dynamics

- Physics
- 2022

Monitored quantum system with measurements can undergo dynamical phase transitions in the entanglement properties of quantum trajectories conditional on measurement outcomes. These entanglement…

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