Understanding the role of correlations in quantum systems is both a fundamental challenge as well as of high practical relevance for the control of multi-particle quantum systems. Whereas a lot of research has been devoted to study the various types of correlations that can be present in the states of quantum systems, in this work we introduce a general and rigorous method to quantify the amount of correlations in the dynamics of quantum systems. Using a resource-theoretical approach, we introduce a suitable quantifier and characterize the properties of correlated dynamics. Furthermore, we benchmark our method by applying it to the paradigmatic case of two atoms weakly coupled to the electromagnetic radiation field, and illustrate its potential use to detect and assess spatial noise correlations in quantum computing architectures.Understanding the role of correlations in quantum systems is both a fundamental challenge as well as of high practical relevance for the control of multi-particle quantum systems. Whereas a lot of research has been devoted to study the various types of correlations that can be present in the states of quantum systems, in this work we introduce a general and rigorous method to quantify the amount of correlations in the dynamics of quantum systems. Using a resource-theoretical approach, we introduce a suitable quantifier and characterize the properties of correlated dynamics. Furthermore, we benchmark our method by applying it to the paradigmatic case of two atoms weakly coupled to the electromagnetic radiation field, and illustrate its potential use to detect and assess spatial noise correlations in quantum computing architectures.

Jan 1, 201512 citations

Experimental quantification of spatial correlations in quantum dynamics

Lukas Postler, ́Angel Rivas, Philipp Schindler +6 more

Correlations between different partitions of quantum systems play a central role in a variety of many-body quantum systems, and they have been studied exhaustively in experimental and theoretical research. Here, we investigate dynamical correlations in the time evolution of multiple parts of a composite quantum system. A rigorous measure to quantify correlations in quantum dynamics based on a full tomographic reconstruction of the quantum process has been introduced recently [Á. Rivas et al., New Journal of Physics, 17(6) 062001 (2015).]. In this work, we derive a lower bound for this correlation measure, which does not require full knowledge of the quantum dynamics. Furthermore we also extend the correlation measure to multipartite systems. We directly apply the developed methods to a trapped ion quantum information processor to experimentally characterize the correlations in quantum dynamics for two- and four-qubit systems. The method proposed and demonstrated in this work is scalable, platform-independent and applicable to other composite quantum systems and quantum information processing architectures. We apply the method to estimate spatial correlations in environmental noise processes, which are crucial for the performance of quantum error correction procedures.Correlations between different partitions of quantum systems play a central role in a variety of many-body quantum systems, and they have been studied exhaustively in experimental and theoretical research. Here, we investigate dynamical correlations in the time evolution of multiple parts of a composite quantum system. A rigorous measure to quantify correlations in quantum dynamics based on a full tomographic reconstruction of the quantum process has been introduced recently [Á. Rivas et al., New Journal of Physics, 17(6) 062001 (2015).]. In this work, we derive a lower bound for this correlation measure, which does not require full knowledge of the quantum dynamics. Furthermore we also extend the correlation measure to multipartite systems. We directly apply the developed methods to a trapped ion quantum information processor to experimentally characterize the correlations in quantum dynamics for two- and four-qubit systems. The method proposed and demonstrated in this work is scalable, platform-independent and applicable to other composite quantum systems and quantum information processing architectures. We apply the method to estimate spatial correlations in environmental noise processes, which are crucial for the performance of quantum error correction procedures.

Jan 1, 201815 citations

Experimental quantification of spatial correlations in quantum dynamics

Lukas Postler, Ángel Rivas, Philipp Schindler +6 more

arXiv:1806.08088QuantumSep 3, 201817 citations

Quantum State Multi-Modal Correlation Analysis

Jincheng Zhang

This paper investigates the intricate correlations within multi-modal quantum states, presenting a novel theoretical framework and analytical methodology. The core of the research lies in applying quantum information theory and statistical physics to model and understand the complex behaviors inherent in multi-modal quantum systems. We aim to move beyond traditional approaches by establishing a robust mathematical framework for quantifying and characterizing multi-modal entanglement and correlations, specifically focusing on scenarios where multiple quantum systems are linked. The developed methods offer a new perspective on manipulating and controlling these systems, with potential implications for quantum computation, quantum communication, and fundamental quantum information theory. The key contributions include a generalized correlation function, a multi-modal entanglement measure, and an approach to analyzing the dynamics of multi-modal quantum systems. The work explores the connections between classical statistical mechanics and quantum entanglement in these systems, providing insights into the emergence of correlations at the quantum level. ---This paper investigates the intricate correlations within multi-modal quantum states, presenting a novel theoretical framework and analytical methodology. The core of the research lies in applying quantum information theory and statistical physics to model and understand the complex behaviors inherent in multi-modal quantum systems. We aim to move beyond traditional approaches by establishing a robust mathematical framework for quantifying and characterizing multi-modal entanglement and correlations, specifically focusing on scenarios where multiple quantum systems are linked. The developed methods offer a new perspective on manipulating and controlling these systems, with potential implications for quantum computation, quantum communication, and fundamental quantum information theory. The key contributions include a generalized correlation function, a multi-modal entanglement measure, and an approach to analyzing the dynamics of multi-modal quantum systems. The work explores the connections between classical statistical mechanics and quantum entanglement in these systems, providing insights into the emergence of correlations at the quantum level. ---

Sep 5, 20260 citations

Title: Multi-Scale Quantum Dynamics with Adaptive Correlation

Jincheng Zhang

Quantum dynamics, the evolution of a quantum system over time, presents a significant challenge for theoretical understanding. Traditional approaches often simplify the system, neglecting the crucial role of correlations between particles at different scales. This paper introduces a novel model, "Multi-Scale Quantum Dynamics with Adaptive Correlation," designed to address this limitation by incorporating a dynamically adjustable correlation matrix. This matrix adapts to the system's state, ensuring consistent behavior across all scales. We propose a method for quantifying and controlling these correlations, offering a more realistic and insightful representation of quantum systems. The model's core principle lies in a scale-dependent correlation matrix that evolves based on the system's state, promoting a holistic view of quantum behavior. This approach has the potential to significantly advance our understanding of complex quantum phenomena.Quantum dynamics, the evolution of a quantum system over time, presents a significant challenge for theoretical understanding. Traditional approaches often simplify the system, neglecting the crucial role of correlations between particles at different scales. This paper introduces a novel model, "Multi-Scale Quantum Dynamics with Adaptive Correlation," designed to address this limitation by incorporating a dynamically adjustable correlation matrix. This matrix adapts to the system's state, ensuring consistent behavior across all scales. We propose a method for quantifying and controlling these correlations, offering a more realistic and insightful representation of quantum systems. The model's core principle lies in a scale-dependent correlation matrix that evolves based on the system's state, promoting a holistic view of quantum behavior. This approach has the potential to significantly advance our understanding of complex quantum phenomena.

Sep 6, 20260 citations

Dynamics of spatially indistinguishable particles and quantum entanglement protection

Farzam Nosrati, Alessia Castellini, G. Compagno +1 more

A complete treatment of open quantum systems made of identical particles has remained elusive due to the intrinsic problem of these particles being individually unaddressable. Filling this gap is essential for the full characterization of quantum networks which are typically built by identical subsystems. We provide a general framework which allows one to obtain the dynamics of $N$ noninteracting spatially indistinguishable particles locally coupled to separated environments. This framework is universal, being valid for both bosons and fermions and for any type of system-environment interaction. It is applied to study the dynamics of two identical qubits under paradigmatic Markovian noises, such as phase damping, depolarization, and amplitude damping. We find that spatial indistinguishability of identical qubits is a controllable inherent property of the system which protects exploitable quantum entanglement against detrimental noise.A complete treatment of open quantum systems made of identical particles has remained elusive due to the intrinsic problem of these particles being individually unaddressable. Filling this gap is essential for the full characterization of quantum networks which are typically built by identical subsystems. We provide a general framework which allows one to obtain the dynamics of $N$ noninteracting spatially indistinguishable particles locally coupled to separated environments. This framework is universal, being valid for both bosons and fermions and for any type of system-environment interaction. It is applied to study the dynamics of two identical qubits under paradigmatic Markovian noises, such as phase damping, depolarization, and amplitude damping. We find that spatial indistinguishability of identical qubits is a controllable inherent property of the system which protects exploitable quantum entanglement against detrimental noise.

arXiv:2008.07471Physical Review ADec 30, 202023 citations

N

noninteracting spatially indistinguishable particles locally coupled to separated environments. This framework is universal, being valid for both bosons and fermions and for any type of system-environment interaction. It is applied to study the dynamics of two identical qubits under paradigmatic Markovian noises, such as phase damping, depolarization, and amplitude damping. We find that spatial indistinguishability of identical qubits is a controllable inherent property of the system which protects exploitable quantum entanglement against detrimental noise.