Non-additivity in classical-quantum wiretap channels
- URL: http://arxiv.org/abs/2002.06580v2
- Date: Mon, 6 Jul 2020 15:06:06 GMT
- Title: Non-additivity in classical-quantum wiretap channels
- Authors: Arkin Tikku and Mario Berta and Joseph M. Renes
- Abstract summary: We study hybrid classical-quantum wiretap channels in order to witness non-additivity phenomena in quantum Shannon theory.
For wiretap channels with quantum inputs but classical outputs, we prove that the characterization of the capacity in terms of the private information stays single-letter.
- Score: 12.354076490479514
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Due to Csiszar and Koerner, the private capacity of classical wiretap
channels has a single-letter characterization in terms of the private
information. For quantum wiretap channels, however, it is known that
regularization of the private information is necessary to reach the capacity.
Here, we study hybrid classical-quantum wiretap channels in order to resolve to
what extent quantum effects are needed to witness non-additivity phenomena in
quantum Shannon theory. For wiretap channels with quantum inputs but classical
outputs, we prove that the characterization of the capacity in terms of the
private information stays single-letter. Hence, entangled input states are of
no asymptotic advantage in this setting. For wiretap channels with classical
inputs, we show by means of explicit examples that the private information
already becomes non-additive when either one of the two receivers becomes
quantum (with the other receiver staying classical). This gives non-additivity
examples that are not caused by entanglement and illustrates that quantum
adversaries are strictly different from classical adversaries in the wiretap
model.
Related papers
- Quantum-classical correspondence in quantum channels [0.0]
Quantum channels describe subsystem or open system evolution.
Four classical Koopman channels are identified that are analogs of the 4 possible quantum channels in a bipartite setting.
arXiv Detail & Related papers (2024-07-19T06:53:45Z) - Fully quantum arbitrarily varying channel coding for entanglement-assisted communication [0.0]
We study the problem of entanglement-assisted capacity in the presence of system uncertainty.
We find that, under the assumption of a finite environment dimension, it is equal to a corresponding compound capacity.
Our results imply that in certain fully quantum arbitrarily varying channel models, the entanglement-assisted capacity can be positive while the classical capacity is equal to zero.
arXiv Detail & Related papers (2024-04-12T02:10:04Z) - On Simultaneous Information and Energy Transmission through Quantum Channels [15.387256204743407]
We introduce the quantum-classical analogue of the capacity-power function.
We generalize results in classical information theory for transmitting classical information through noisy channels.
arXiv Detail & Related papers (2023-09-24T16:46:47Z) - Faithfulness and sensitivity for ancilla-assisted process tomography [0.0]
A system-ancilla bipartite state capable of containing the complete information of an unknown quantum channel acting on the system is called faithful.
We complete the proof of the equivalence and introduce the generalization of faithfulness to various classes of quantum channels.
arXiv Detail & Related papers (2022-06-13T04:19:22Z) - The platypus of the quantum channel zoo [12.4245398967236]
We study a simple, low-dimensional family of quantum channels with exotic quantum information-theoretic features.
We generalize the qutrit channel in two ways, and the resulting channels and their capacities display similarly rich behavior.
arXiv Detail & Related papers (2022-02-16T23:54:07Z) - Commitment capacity of classical-quantum channels [70.51146080031752]
We define various notions of commitment capacity for classical-quantum channels.
We prove matching upper and lower bound on it in terms of the conditional entropy.
arXiv Detail & Related papers (2022-01-17T10:41:50Z) - Secure Two-Party Quantum Computation Over Classical Channels [63.97763079214294]
We consider the setting where the two parties (a classical Alice and a quantum Bob) can communicate only via a classical channel.
We show that it is in general impossible to realize a two-party quantum functionality with black-box simulation in the case of malicious quantum adversaries.
We provide a compiler that takes as input a classical proof of quantum knowledge (PoQK) protocol for a QMA relation R and outputs a zero-knowledge PoQK for R that can be verified by classical parties.
arXiv Detail & Related papers (2020-10-15T17:55:31Z) - Fault-tolerant Coding for Quantum Communication [71.206200318454]
encode and decode circuits to reliably send messages over many uses of a noisy channel.
For every quantum channel $T$ and every $eps>0$ there exists a threshold $p(epsilon,T)$ for the gate error probability below which rates larger than $C-epsilon$ are fault-tolerantly achievable.
Our results are relevant in communication over large distances, and also on-chip, where distant parts of a quantum computer might need to communicate under higher levels of noise.
arXiv Detail & Related papers (2020-09-15T15:10:50Z) - Quantum Channel State Masking [78.7611537027573]
Communication over a quantum channel that depends on a quantum state is considered when the encoder has channel side information (CSI) and is required to mask information on the quantum channel state from the decoder.
A full characterization is established for the entanglement-assisted masking equivocation region, and a regularized formula is given for the quantum capacity-leakage function without assistance.
arXiv Detail & Related papers (2020-06-10T16:18:03Z) - Quantum noise protects quantum classifiers against adversaries [120.08771960032033]
Noise in quantum information processing is often viewed as a disruptive and difficult-to-avoid feature, especially in near-term quantum technologies.
We show that by taking advantage of depolarisation noise in quantum circuits for classification, a robustness bound against adversaries can be derived.
This is the first quantum protocol that can be used against the most general adversaries.
arXiv Detail & Related papers (2020-03-20T17:56:14Z) - Permutation Enhances Classical Communication Assisted by Entangled
States [67.12391801199688]
We show that the capacity satisfies the strong converse property and thus the formula serves as a sharp dividing line between achievable and unachievable rates of communication.
As examples, we derive analytically the classical capacity of various quantum channels of interests.
arXiv Detail & Related papers (2020-01-07T01:49:31Z)
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.