English
Related papers

Related papers: Getting Something Out of Nothing

200 papers

One of the most prominent techniques to enhance the performance of practical quantum key distribution (QKD) systems with laser sources is the decoy-state method. Current decoy-state QKD setups operate at GHz repetition rates, a regime where…

Quantum Physics · Physics 2023-04-13 Xoel Sixto , Víctor Zapatero , Marcos Curty

The core of security proofs of quantum key distribution (QKD) is the estimation of a parameter that determines the amount of privacy amplification that the users need to apply in order to distill a secret key. To estimate this parameter…

Quantum Physics · Physics 2022-10-24 Guillermo Currás-Lorenzo , Álvaro Navarrete , Margarida Pereira , Kiyoshi Tamaki

Quantum key distribution is a way to distribute secret keys to distant users with information theoretic security and key rates suitable for real-world applications. Its rate-distance figure, however, is limited by the natural loss of the…

Quantum Physics · Physics 2018-09-12 Kiyoshi Tamaki , Hoi-Kwong Lo , Wenyuan Wang , Marco Lucamarini

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

Decoy-state quantum key distribution (QKD) is a standard technique in current quantum cryptographic implementations. Unfortunately, existing experiments have two important drawbacks: the state preparation is assumed to be perfect without…

Quantum Physics · Physics 2015-09-09 Feihu Xu , Kejin Wei , Shihan Sajeed , Sarah Kaiser , Shihai Sun , Zhiyuan Tang , Li Qian , Vadim Makarov , Hoi-Kwong Lo

Recent oracle separations [Kretschmer, TQC'21, Kretschmer et. al., STOC'23] have raised the tantalizing possibility of building quantum cryptography from sources of hardness that persist even if the polynomial hierarchy collapses. We…

Quantum Physics · Physics 2024-10-11 Dakshita Khurana , Kabir Tomer

In this paper, we investigate properties of some multi-particle entangled states and, from the properties applying the secret sharing present a new type of quantum key distribution protocols as generalization of quantum key distribution…

Quantum Physics · Physics 2007-05-23 Sora Choi , Jinsoo Kim , Dong Pyo Chi

We discuss a quantum key distribution scheme in which small phase and amplitude modulations of quantum limited, CW light beams carry the key information. We identify universal constraints on the level of shared information between the…

Quantum Physics · Physics 2007-05-23 T. C. Ralph

We develop a theory for long-distance quantum key distribution based on concatenated entanglement swapping using parametric down-conversion sources and show numerical results of our model. The model incorporates practical resources…

Quantum Physics · Physics 2016-02-09 Aeysha Khalique , Barry C. Sanders

The decoy state protocol has been considered to be one of the most important methods to protect the security of quantum key distribution (QKD) with a weak coherent source. Here we test two experimental approaches to generating the decoy…

Quantum Physics · Physics 2018-09-18 Anqi Huang , Shi-Hai Sun , Zhihong Liu , Vadim Makarov

We Haar uniformly generate random states of various ranks and study their performance in an entanglement-based quantum key distribution (QKD) task. In particular, we analyze the efficacy of random two-qubit states in realizing…

Quantum Physics · Physics 2023-02-14 Subhankar Bera , Shashank Gupta , A. S. Majumdar

Quantum key distribution (QKD) enables the establishment of secret keys between users connected via a channel vulnerable to eavesdropping, with information-theoretic security, that is, independently of the power of a malevolent party. QKD…

Secure quantum communication protocols based on a prepare-and-measure scheme employ mutually unbiased bases. In these protocols, many runs, in which different participants measure in different bases, simply go wasted. In this paper, we show…

Quantum Physics · Physics 2023-05-09 Rajni Bala , Sooryansh Asthana , V. Ravishankar

A promising platform for semi-device-independent quantum information is prepare-and-measure experiments restricted only by a bound on the energy of the communication. Here, we investigate the role of shared entanglement in such scenarios.…

Quantum Physics · Physics 2026-03-19 Carles Roch I Carceller , Armin Tavakoli

The laws of quantum mechanics allow unconditionally secure key distribution protocols. Nevertheless, security proofs of traditional quantum key distribution (QKD) protocols rely on a crucial assumption, the trustworthiness of the quantum…

Quantum Physics · Physics 2014-10-08 Umesh Vazirani , Thomas Vidick

Quantum key distribution can provide unconditionally secure key exchange for remote users in theory. In practice, however, in most quantum key distribution systems, quantum hackers might steal the secure keys by listening to the side…

We investigate the security of continuous-variable (CV) quantum key distribution (QKD) using coherent states in the presence of quadrature excess noise. We consider an eavesdropping attack which uses a linear amplifier and beam splitter.…

Quantum Physics · Physics 2009-11-11 Ryo Namiki , Takuya Hirano

We consider the security of continuous-variable quantum key distribution using thermal (or noisy) Gaussian resource states. Specifically, we analyze this against collective Gaussian attacks using direct and reverse reconciliation where both…

Quantum Physics · Physics 2013-04-17 Christian Weedbrook , Stefano Pirandola , Timothy C. Ralph

Quantum key distribution (QKD) enables the generation of secure keys between two distant users. Security proof of QKD against general coherent attacks is challenging, while the one against collective attacks is much easier. As an effective…

Quantum Physics · Physics 2024-10-01 Yang-Guang Shan , Zhen-Qiang Yin , Shuang Wang , Wei Chen , De-Yong He , Guang-Can Guo , Zheng-Fu Han

We have designed and realized a prototype that implements a continuous-variable quantum key distribution protocol based on coherent states and reverse reconciliation. The system uses time and polarization multiplexing for optimal…