Semi-device-independent certification of indefinite causal order in a photonic quantum switch

Abstract

We report an experimental certification of indefinite causal order that relies only on the characterization of the operations of a single party. We do so in the semi-device-independent scenario with the fewest possible assumptions of characterization of the parties' local operations in which indefinite causal order can be demonstrated with the quantum switch. To achieve this result, we introduce the concept of semi-device-independent causal inequalities and show that the correlations generated in a photonic quantum switch, in which all parties are able to collect local outcome statistics, achieve a violation of this inequality of 224 standard deviations. This result consists of the experimental demonstration of indefinite causal order with the fewest device-characterization assumptions to date.

arXiv comment9 + 4 pages, 5 + 1 figures. Close to the published version

References in corpus (42)

• Bell nonlocality
• Bell Inequalities and the Separability Criterion
• Gravitationally-induced entanglement between two massive particles is sufficient evidence of quantum effects in gravity
• Quantum correlations with no causal order
• Experimental criteria for steering and the Einstein-Podolsky-Rosen paradox
• Quantum computations without definite causal structure
• Theoretical framework for quantum networks
• Quantum Circuits Architecture
• Quantifying Einstein-Podolsky-Rosen steering
• Non-Markovian quantum processes: complete framework and efficient characterisation
• Experimental Superposition of Orders of Quantum Gates
• Computational advantage from quantum-controlled ordering of gates
• 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
• Quantum Channels with Memory
• Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure
• Exponential Communication Complexity Advantage from Quantum Superposition of the Direction of Communication
• Witnessing causal nonseparability
• On the possibility of laboratory evidence for quantum superposition of geometries
• Quantum Metrology with Indefinite Causal Order
• Causal and causally separable processes
• Experimental transmission of quantum information using a superposition of causal orders
• Experimental Quantum Switching for Exponentially Superior Quantum Communication Complexity
• Quantum superposition of the order of parties as a communication resource
• The simplest causal inequalities and their violation
• Experimental Quantum Communication Enhancement by Superposing Trajectories
• Communicating via ignorance: Increasing communication capacity via superposition of order
• Reversing Unknown Quantum Transformations: Universal Quantum Circuit for Inverting General Unitary Operations
• Computational advantage from quantum superposition of multiple temporal orders of photonic gates
• Time-delocalized quantum subsystems and operations: on the existence of processes with indefinite causal structure in quantum mechanics
• Strict hierarchy between parallel, sequential, and indefinite-causal-order strategies for channel discrimination
• Quantum circuits with classical versus quantum control of causal order
• Experimentally feasible computational advantage from quantum superposition of gate orders
• Functional Quantum Computing: An Optical Approach
• Causal orders, quantum circuits and spacetime: distinguishing between definite and superposed causal orders
• Experimental entanglement of temporal order
• Unitary channel discrimination beyond group structures: Advantages of sequential and indefinite-causal-order strategies
• Semi-device-independent certification of indefinite causal order
• Semi-Device-Independent Certification of Causal Nonseparability with Trusted Quantum Inputs
• Device-independent certification of indefinite causal order in the quantum switch

Cited by in corpus (12)

• Experimental Aspects of Indefinite Causal Order in Quantum Mechanics
• Higher-order Process Matrix Tomography of a passively-stable Quantum SWITCH
• Demonstration of a quantum SWITCH in a Sagnac configuration
• Reassessing thermodynamic advantage from indefinite causal order
• Experimental superposition of time directions
• Comparing the quantum switch and its simulations with energetically-constrained operations
• Memory in quantum processes with indefinite time direction and causal order
• Indefinite causal key distribution
• Toward an Experimental Device-Independent Verification of Indefinite Causal Order
• Possibilistic and maximal indefinite causal order in the quantum switch
• Simulating the quantum switch with quantum circuits is computationally hard
• Entropic uncertainty under indefinite causal order and input-output direction