Backaction-free measurement of quantum correlations via quantum time-domain interferometry

• URL: http://arxiv.org/abs/2003.11900v1
• Date: Thu, 26 Mar 2020 13:36:48 GMT
• Title: Backaction-free measurement of quantum correlations via quantum time-domain interferometry
• Authors: Salvatore Castrignano and J\"org Evers
• Abstract summary: Time-domain interferometry (TDI) is a method to probe space-time correlations among particles in condensed matter systems. Here, we show that a recently developed quantum version of TDI (QTDI) can access the full quantum-mechanical two-time correlations without backaction.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Time-domain interferometry (TDI) is a method to probe space-time correlations among particles in condensed matter systems. Applying TDI to quantum systems raises the general question, whether two-time correlations can be reliably measured without adverse impact of the measurement backaction onto the dynamics of the system. Here, we show that a recently developed quantum version of TDI (QTDI) indeed can access the full quantum-mechanical two-time correlations without backaction. We further generalize QTDI to weak classical continuous-mode coherent input states, alleviating the need for single-photon input fields. Finally, we interpret our results by splitting the space-time correlations into two parts. While the first one is associated to projective measurements and thus insensitive to backaction, we identify the second contribution as arising from the coherence properties of the state of the probed target system, such that it is perturbed or even destroyed by measurements on the system.

Related papers

• Theory of the correlated quantum Zeno effect in a monitored qubit dimer [41.94295877935867]
  We show how the competition between two measurement processes give rise to two distinct Quantum Zeno (QZ) regimes. We develop a theory based on a Gutzwiller ansatz for the wavefunction that is able to capture the structure of the Hilbert phase diagram. We show how the two QZ regimes are intimately connected to the topology of the flow of the underlying non-Hermitian Hamiltonian governing the no-click evolution.
  arXiv  Detail & Related papers  (2025-03-28T19:44:48Z)
• Cahier de l'Institut Pascal: Noisy Quantum Dynamics and Measurement-Induced Phase Transitions [44.99833362998488]
  We provide an analysis of recent results in the context of measurement-induced phase transitions in quantum systems. Recent results show how varying the rate of projective measurements can induce phase transitions. We present results on the non-local effects of local measurements by examining the field theory of critical ground states in Tomonaga-Luttinger liquids.
  arXiv  Detail & Related papers  (2024-09-10T08:10:25Z)
• Enhanced Entanglement in the Measurement-Altered Quantum Ising Chain [46.99825956909532]
  Local quantum measurements do not simply disentangle degrees of freedom, but may actually strengthen the entanglement in the system. This paper explores how a finite density of local measurement modifies a given state's entanglement structure.
  arXiv  Detail & Related papers  (2023-10-04T09:51:00Z)
• Quantum Causal Inference with Extremely Light Touch [0.0]
  We give an explicit quantum causal inference scheme using quantum observations alone. We derive a closed-form expression for the space-time pseudo-density matrix associated with many times and qubits. We prove that if there is no signalling between two subsystems, the associated reduced state of the pseudo-density matrix cannot have negativity.
  arXiv  Detail & Related papers  (2023-03-19T02:59:05Z)
• Evolution of many-body systems under ancilla quantum measurements [58.720142291102135]
  We study the concept of implementing quantum measurements by coupling a many-body lattice system to an ancillary degree of freedom. We find evidence of a disentangling-entangling measurement-induced transition as was previously observed in more abstract models.
  arXiv  Detail & Related papers  (2023-03-13T13:06:40Z)
• Bell inequalities with overlapping measurements [52.81011822909395]
  We study Bell inequalities where measurements of different parties can have overlap. This allows to accommodate problems in quantum information. The scenarios considered show an interesting behaviour with respect to Hilbert space dimension, overlap, and symmetry.
  arXiv  Detail & Related papers  (2023-03-03T18:11:05Z)
• Thermodynamics of a continuously monitored double quantum dot heat engine in the repeated interactions framework [0.0]
  We study a double quantum dot (DQD) connected to two macroscopic fermionic thermal reservoirs. We show that the local master equation of the DQD can alternatively be derived in the framework of repeated interactions.
  arXiv  Detail & Related papers  (2022-12-20T12:03:22Z)
• Snapshotting Quantum Dynamics at Multiple Time Points [10.226937603741474]
  We propose a method to extract dynamic information from a quantum system at intermediate time points. We reconstruct a multi-time quasi-probability distribution (QPD) that correctly recovers the probability at the respective time points.
  arXiv  Detail & Related papers  (2022-07-13T10:28:01Z)
• Finite resolution ancilla-assisted measurements of quantum work distributions [77.34726150561087]
  We consider an ancilla-assisted protocol measuring the work done on a quantum system driven by a time-dependent Hamiltonian. We consider system Hamiltonians which both commute and do not commute at different times, finding corrections to fluctuation relations like the Jarzynski equality and the Crooks relation.
  arXiv  Detail & Related papers  (2021-11-30T15:08:25Z)
• Generalized quantum measurements with matrix product states: Entanglement phase transition and clusterization [58.720142291102135]
  We propose a method for studying the time evolution of many-body quantum lattice systems under continuous and site-resolved measurement. We observe a peculiar phenomenon of measurement-induced particle clusterization that takes place only for frequent moderately strong measurements, but not for strong infrequent measurements.
  arXiv  Detail & Related papers  (2021-04-21T10:36:57Z)
• From Non-Hermitian Linear Response to Dynamical Correlations and Fluctuation-Dissipation Relations in Quantum Many-Body Systems [0.0]
  We propose a technique for measuring unequal-time anti-commutators using the linear response of a system to a non-Hermitian perturbation. We relate the scheme to the quantum Zeno effect and weak measurements, and illustrate possible implementations.
  arXiv  Detail & Related papers  (2021-04-08T18:00:06Z)
• Non-destructively probing the thermodynamics of quantum systems with qumodes [0.6144680854063939]
  In quantum systems there is often a destruction of the system itself due to the means of measurement. One approach to circumventing this is the use of ancillary probes that couple to the system under investigation. We highlight means by which continuous variable quantum modes (qumodes) can be employed to probe the thermodynamics of quantum systems in and out of equilibrium.
  arXiv  Detail & Related papers  (2017-07-13T17:57:11Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.