Experimental transmission of quantum information using a superposition of causal orders

Abstract

Communication in a network generally takes place through a sequence of intermediate nodes connected by communication channels. In the standard theory of communication, it is assumed that the communication network is embedded in a classical spacetime, where the relative order of different nodes is well-defined. In principle, a quantum theory of spacetime could allow the order of the intermediate points between sender and receiver to be in a coherent superposition. Here we experimentally realise a table-top simulation of this exotic possibility on a photonic system, demonstrating high-fidelity transmission of quantum information over two noisy channels arranged in a superposition of two alternative causal orders.

arXiv comment8 pages, 5 figures. Accepted for publication in Physical review letters

References in corpus (23)

• A Spin Entanglement Witness for Quantum Gravity
• Prescription for experimental determination of the dynamics of a quantum black box
• The capacity of the noisy quantum channel
• Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
• Quantum correlations with no causal order
• Quantum data processing and error correction
• Quantum computations without definite causal structure
• Experimental Superposition of Orders of Quantum Gates
• Tomography of Quantum Operations
• Experimental Verification of an Indefinite Causal Order
• Enhanced communication with the assistance of indefinite causal order
• Perfect discrimination of no-signalling channels via quantum superposition of causal structures
• Indefinite Causal Order in a Quantum Switch
• Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure
• On the possibility of laboratory evidence for quantum superposition of geometries
• Quantum Shannon theory with superpositions of trajectories
• Communication through quantum-controlled noise
• Time-delocalized quantum subsystems and operations: on the existence of processes with indefinite causal structure in quantum mechanics
• Communication Enhancement Through Quantum Coherent Control of $N$ Channels in an Indefinite Causal-order Scenario
• Maximum-likelihood reconstruction of CP maps
• Interference of Quantum Channels
• Error Filtration and Entanglement Purification for Quantum Communication
• Two-way communication with a single quantum particle

Cited by in corpus (84)

• Quantum Metrology with Indefinite Causal Order
• Quantum Refrigeration with Indefinite Causal Order
• Indefinite causal order enables perfect quantum communication with zero capacity channels
• Experimental Quantum Communication Enhancement by Superposing Trajectories
• Communication through coherent control of quantum channels
• Communicating via ignorance: Increasing communication capacity via superposition of order
• Computational advantage from quantum superposition of multiple temporal orders of photonic gates
• Resource theories of communication
• Quantum circuits with classical versus quantum control of causal order
• Cyclic Quantum Causal Models
• Experimentally feasible computational advantage from quantum superposition of gate orders
• Noisy quantum metrology with the assistance of indefinite causal order
• Work extraction from coherently activated maps via quantum switch
• Quantum and Classical Data Transmission through Completely Depolarising Channels in a Superposition of Cyclic Orders
• Experiments on quantum causality
• Experimental Aspects of Indefinite Causal Order in Quantum Mechanics
• Learning Temporal Quantum Tomography
• Thermal devices powered by generalized measurements with indefinite causal order
• Classical Communications with Indefinite Causal Order for $N$ completely depolarizing channels
• Beyond Shannon Limits: Quantum Communications through Quantum Paths
• Random-Receiver Quantum Communication
• Indefinite causal order for quantum metrology with quantum thermal noise
• Noncausal Page-Wootters circuits
• Measuring incompatibility and clustering quantum observables with a quantum switch
• Semi-device-independent certification of indefinite causal order in a photonic quantum switch
• Exploring quantum thermodynamics with NMR
• Higher-order Process Matrix Tomography of a passively-stable Quantum SWITCH
• Evading noise in multiparameter quantum metrology with indefinite causal order
• Demonstration of a quantum SWITCH in a Sagnac configuration
• Superposed Quantum Error Mitigation
• Enhancing Quantum Computation via Superposition of Quantum Gates
• Interferometric Approach to Open Quantum Systems and Non-Markovian Dynamics
• Controlled quantum operations and combs, and their applications to universal controllization of divisible unitary operations
• Reassessing the advantage of indefinite causal orders for quantum metrology
• Reassessing thermodynamic advantage from indefinite causal order
• Indefinite Causal Orders from Superpositions in Time
• Experimental demonstration of input-output indefiniteness in a single quantum device
• Reassessing the computational advantage of quantum-controlled ordering of gates
• Quantum communication through devices with indefinite input-output direction
• Existence of processes violating causal inequalities on time-delocalised subsystems
• Embedding cyclic information-theoretic structures in acyclic spacetimes: no-go results for indefinite causality
• Comparing the quantum switch and its simulations with energetically-constrained operations
• Fundamental limits for realising quantum processes in spacetime
• Experimentally demonstrating indefinite causal order algorithms to solve the generalized Deutsch's problem
• Semi-Device-Independent Certification of Causal Nonseparability with Trusted Quantum Inputs
• Quantum switch instabilities with an open control
• Classical communication through quantum causal structures
• Quantum switch in the gravity of Earth
• Quantum communication using a quantum switch of quantum switches
• Deterministic generation of multi-qubit entangled states among distant parties using indefinite causal order
• Breaking the limits of purification: Postselection enhances heat-bath algorithmic cooling
• Memory in quantum processes with indefinite time direction and causal order
• Quantum networks boosted by entanglement with a control system
• The SWITCH test for discriminating quantum evolutions
• Activation of thermal states by coherently controlled thermalization processes
• Practical computational advantage from the quantum switch on a generalized family of promise problems
• Experimental Communication Through Superposition of Quantum Channels
• Quantum chicken-egg dilemmas: Delayed-choice causal order and the reality of causal non-separability
• A no-go theorem for superpositions of causal orders
• Quantum Metrology with Coherent Superposition of Two Different Coded Channels
• No-signalling constrains quantum computation with indefinite causal structure
• The quantum switch is uniquely defined by its action on unitary operations
• Experimental implementation of arbitrary entangled operations
• Indefinite causal order for quantum phase estimation with Pauli noise
• Indefinite Time Directed Quantum Metrology
• Superpositions of thermalisations in relativistic quantum field theory
• Quantifying Causal Influence in Quantum Mechanics
• Toward an Experimental Device-Independent Verification of Indefinite Causal Order
• Multifold behavior of the information transmission by the quantum 3-switch
• Background Independence and Quantum Causal Structure
• Simulating the quantum switch with quantum circuits is computationally hard
• Quantum switch as a thermodynamic resource in the context of passive states
• Quantum Paths: a Quantum Walk approach
• Sequential device-independent certification of indefinite causal order
• Causal nonseparability and its implications for spatiotemporal relations
• Enhancement of non-Stabilizerness within Indefinite Causal Order
• A de Finetti theorem for quantum causal structures
• Entropic uncertainty under indefinite causal order and input-output direction
• Optimal Thermalization under Indefinite Causal Order with Identical and Asymmetric Baths
• Witnessing latent time correlations with a single quantum particle
• Refrigeration with Indefinite Causal Orders on a Cloud Quantum Computer
• Distributed Quantum Dense Coding Enhanced With Non-classical Routing
• Causality in a qubit-based quantum switch
• Correlations in a quantum switch-based heat engine with measurements: A proof-of-principle demonstration