English
Related papers

Related papers: Security improvement of using modified coherent st…

200 papers

Quantum-based cryptographic protocols are often said to enjoy security guaranteed by the fundamental laws of physics. However, even carefully designed quantum-based cryptographic schemes may be susceptible to subtle attacks that are outside…

Quantum Physics · Physics 2007-05-23 Hoi-Kwong Lo , Tsz-Mei Ko

A quantum secure direct communication network scheme is proposed with quantum superdense coding and decoy photons. The servers on a passive optical network prepare and measure the quantum signal, i.e., a sequence of the $d$-dimensional Bell…

Quantum Physics · Physics 2015-06-26 Fu-Guo Deng , Xi-Han Li , Chun-Yan Li , Ping Zhou , Hong-Yu Zhou

We show that weakly entangled states can improve communication over a qubit channel using only separate, interference-free, measurements of individual photons. We introduce a communication task corresponding to the cryptographic primitive…

We investigate performances of pure continuous variable states in discriminating thermal and identity channels by comparing their M-copy error probability bounds. This offers us a simplified mathematical analysis for quantum target…

Quantum Physics · Physics 2009-07-10 A. R. Usha Devi , A. K. Rajagopal

We implement a decoy-state quantum key distribution scheme using a telecom C-band single-emitter source. The decoy states are created by varying the optical excitation of the quantum emitter to modulate the photon number distribution. We…

This paper presents a new encryption scheme called Compact Coding that encodes information in time, phase, and intensity domains, simultaneously. While these approaches have previously been used one at a time, the proposed scheme brings to…

Quantum Physics · Physics 2016-07-13 Rasha El Hajj , Pramode Verma , Kam Wai Clifford Chan

We analyze theoretically performance of four-state quantum key distribution protocols implemented with a realistic heralded single-photon source. The analysis assumes a noisy model for the detector heralding generation of individual photons…

Quantum Physics · Physics 2013-07-04 Mikolaj Lasota , Rafal Demkowicz-Dobrzanski , Konrad Banaszek

Quantum memory is a key element for quantum repeaters and linear optical quantum computers. In addition to memory, repeaters and computers also require manipulating quantum states by means of unitary transformations, which is generally…

Quantum Physics · Physics 2009-10-15 A. Delfan Abazari , E. Saglamyurek , R. Ricken , W. Sohler , C. La Mela , W. Tittel

Quantum entanglement is a fundamental resource for quantum information processing and is widely used in quantum communication, quantum computation and quantum metrology. Early research on quantum entanglement mainly focus on qubit states,…

Quantum Physics · Physics 2022-12-02 Linxiang Zhou , Qiao Xu , Tianfeng Feng , Xiaoqi Zhou

It is known that multiphoton states can be protected from decoherence due to a passive loss channel by applying noiseless attenuation before and noiseless amplification after the channel. In this work, we propose the combined use of…

Quantum Physics · Physics 2024-08-07 Saurabh U. Shringarpure , Yong Siah Teo , Hyunseok Jeong

We propose efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection. By these phase encodings, the probability of basis mismatch is reduced and total efficiency is…

Quantum Physics · Physics 2008-09-29 Ryo Namiki , Takuya Hirano

The transport of quantum states is a crucial aspect of information processing systems, facilitating operations such as quantum key distribution and inter-component communication within quantum computers. Most quantum networks rely on…

Noiseless quantum amplifiers are probabilistic quantum devices that enhance amplitude of coherent states without adding any noise, which has far reaching applications in quantum optics and quantum information processing. Here, we report on…

We prove the security of a quantum key distribution scheme based on transmission of squeezed quantum states of a harmonic oscillator. Our proof employs quantum error-correcting codes that encode a finite-dimensional quantum system in the…

Quantum Physics · Physics 2009-11-06 Daniel Gottesman , John Preskill

The practical realizations of BB84 quantum key distribution protocol using single-photon or weak coherent states have normally presented low efficiency, in the meaning that most bits sent by Alice are not useful for the final key. In this…

Quantum Physics · Physics 2007-05-23 Fabio Alencar Mendonca , Rubens Viana Ramos

We introduce a general mapping for encoding quantum communication protocols involving pure states of multiple qubits, unitary transformations, and projective measurements into another set of protocols that employ coherent states of light in…

Quantum Physics · Physics 2014-11-05 Juan Miguel Arrazola , Norbert Lütkenhaus

The discrimination of two nonorthogonal states is a fundamental element for secure and efficient communication. Quantum measurements of nonorthogonal coherent states can enhance information transfer beyond the limits of conventional…

Quantum Physics · Physics 2018-07-16 M. T. DiMario , F. E. Becerra

High-dimensional quantum key distribution (QKD) allows to achieve information-theoretic secure communications, providing high key generation rates which cannot in principle be obtained by QKD protocols with binary encoding. Nonetheless, the…

Quantum Physics · Physics 2020-07-22 I. Vagniluca , B. Da Lio , D. Rusca , D. Cozzolino , Y. Ding , H. Zbinden , A. Zavatta , L. K. Oxenløwe , D. Bacco

In this paper, we introduce a secure optical communication protocol that harnesses quantum correlation within entangled photon pairs. A message written by acting on one of the photons can be read by exclusive measurements of the other…

Quantum Physics · Physics 2024-03-26 Jean Sternberg , Julien Voisin , Charline Roux , Yannick Chassagneux , Maria Ines Amanti

In this paper we present quantum key distribution protocol that, instead of single qubits, uses mesoscopic coherent states of light $|\alpha\rangle$ to encode bit values of a randomly generated key. Given the reference value…

Quantum Physics · Physics 2017-05-04 G. A. Barbosa , J. van de Graaf , P. Mateus , N. Paunković