Related papers: Optical Communication Without Photons
We present truly ultimate limits on covert quantum communication by exploiting quantum-mechanical properties of the Minkowski vacuum in the quantum field theory framework. Our main results are the following: We show how two parties equipped…
Quantum communications bring a paradigm change in internet security by using quantum resources to establish secure keys between parties. Present-day quantum communications networks are mainly point-to-point and use trusted nodes and key…
A simple and efficient protocol for quantum oblivious transfer is proposed. The protocol can easily be implemented with present technology and is secure against cheaters with unlimited computing power provided the receiver does not have the…
Covert communication offers a method to transmit messages in such a way that it is not possible to detect that the communication is happening at all. In this work, we report an experimental demonstration of covert communication that is…
We propose an alignment-free two-party polarization-entanglement transmission scheme for entangled photons by using only linear-optical elements, requiring neither ancillary photons nor calibrated reference frames. The scheme is robust…
Over the past several decades, the proliferation of global classical communication networks has transformed various facets of human society. Concurrently, quantum networking has emerged as a dynamic field of research, driven by its…
We consider the problem of quantum communication mediated by an optical refocusing system, which is schematized as a thin lens with a finite pupil. This model captures the basic features of all those situations in which a signal is either…
It has long been assumed in physics that for information to travel between two parties in empty space, "Alice" and "Bob", physical particles have to travel between them. Here, using the "chained" quantum Zeno effect, we show how, in the…
Counterfactual communication, i.e., communication without particle travelling in the transmission channel, is a bizarre quantum effect. Starting from interaction-free measurements many protocols achieving various tasks from counterfactual…
This letter proposes a novel key distribution protocol with no key exchange in advance, which is secure as the BB84 quantum key distribution protocol. Our protocol utilizes a photon in superposition state for single-bit data transmission…
Encryption prevents unauthorized decoding, but does not ensure stealth---a security demand that a mere presence of a message be undetectable. We characterize the ultimate limit of covert communication that is secure against the most…
We generalize a quantum communication protocol introduced by Bartlett et al. [New. J. Phys. 11, 063013 (2009)] in which two parties communicating do not share a classical reference frame, to the case where changes of their reference frames…
In the present work we investigate the possibility of superluminal information transmission in quantum theory. We give simple and general arguments to prove that the general structure (Hilbert's space plus instantaneous state reduction) of…
We theoretically explore a quantum memory using a single nanoparticle levitated in an optical dipole trap and subjected to feedback cooling. This protocol is realized by storing and retrieving a single photon quantum state from a mechanical…
Quantum information processing (QIP) offers the promise of being able to do things that we cannot do with conventional technology. Here we present a new route for distributed optical QIP, based on generalized quantum non-demolition…
Quantum imaging, one of the pillars of quantum technologies, is well-suited to study sensitive samples which require low-light conditions, like biological tissues. In this context, interaction-free measurements (IFM) allow us infer the…
We propose a method that enables efficient conversion of quantum information frequency between different regions of spectrum of light based on recently demonstrated strong parametric coupling between two narrow-band single-photon pulses…
A theoretical framework of quantum no-key (QNK) protocol has been presented. As its applications, we develop three kinds of QNK protocols: the practical QNK protocols, the QNK protocol based on quantum perfect encryption, and the QNK…
Quantum Teleportation, the transfer of the state of one quantum system to another without direct interaction between both systems, is an important way to transmit information encoded in quantum states and to generate quantum correlations…
By sending systems in specially prepared quantum states, two parties can communicate without an eavesdropper being able to listen. The technique, called quantum cryptography, enables one to verify that the state of the quantum system has…