Indefinite causal key distribution
arXiv:2303.03893 · doi:10.1088/1751-8121/ae1e44
Abstract
We propose a quantum key distribution (QKD) protocol that is carried out in an indefinite causal order (ICO). In QKD, one considers a setup in which two parties, Alice and Bob, share a key with one another in such a way that they can detect whether an eavesdropper, Eve, has learnt anything about the key. To our knowledge, in all QKD protocols proposed until now, Eve is detected by publicly comparing a subset of Alice and Bob's key and checking for errors. We find that a consequence of our protocol is that it is possible to detect eavesdroppers without publicly comparing any information about the key. Indeed, we prove that it is not possible for eavesdroppers, performing any individual attack, to extract useful information about the shared key without inducing a nonzero probability of being detected. We also prove the security of this protocol against a class of individual eavesdropping attacks. The role ICO plays in causing unusual phenomena in quantum technologies is an important question. By considering it we find a two-way QKD protocol that exhibits a similar private detection feature, albeit with some interesting differences. After noting some implications of these differences and discussing some of the practicalities of our protocol, we conclude that this work is best considered as a first step in applying quantum cryptographic ideas in an ICO.
References in corpus (39)
- The Security of Practical Quantum Key Distribution
- Measurement-device-independent quantum key distribution
- Quantum Key Distribution with High Loss: Toward Global Secure Communication
- Secure direct communication using entanglement
- Deterministic Secure Direct Communication Using Entanglement
- Quantum cryptography protocols robust against photon number splitting attacks for weak laser pulses implementations
- Quantum correlations with no causal order
- Quantum computations without definite causal structure
- Fully device independent quantum key distribution
- Secure Deterministic Communication Without Entanglement
- Post-selection technique for quantum channels with applications to quantum cryptography
- 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
- 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
- Practical issues in quantum-key-distribution post-processing
- Witnessing causal nonseparability
- Quantum dynamics as a physical resource
- Quantum Conference Key Agreement: A Review
- Quantum Metrology with Indefinite Causal Order
- Optimum unambiguous discrimination of two mixed quantum states
- Quantum Refrigeration with Indefinite Causal Order
- Indefinite causal order enables perfect quantum communication with zero capacity channels
- Security of two-way quantum key distribution
- Communication through coherent control of quantum channels
- Communication through quantum-controlled noise
- Extracting information from a qubit by multiple observers: Toward a theory of sequential state discrimination
- Unconditional security proof of a deterministic quantum key distribution with a two-way quantum channel
- Resource theories of communication
- Work extraction from coherently activated maps via quantum switch
- Channel capacity enhancement with indefinite causal order
- Experimental Aspects of Indefinite Causal Order in Quantum Mechanics
- Dynamics of quantum causal structures
- Semi-device-independent certification of indefinite causal order in a photonic quantum switch
- Evading noise in multiparameter quantum metrology with indefinite causal order
- Experimental Measurement-Device-Independent Quantum Cryptographic Conferencing