QKD

Anqi Huang - IQC

Quantum key distribution (QKD) is able to achieve information-theoretic security in principle. However, in practice, imperfect devices threaten the security of quantum cryptographic systems. As a promising countermeasure against practical attacks, measurement-device-independent (MDI) QKD is immune to all detector side-channel attacks. Nevertheless, there are some limitations of the MDI QKD protocol. To overcome the technical limitations of MDI QKD, I scrutinized and evaluated other two countermeasures against imperfect detections.

Titas Chanda, Harish-Chandra Research Institute

Emergence of quantum information science has led to a paradigm shift in communication systems. In the past couple of decades, quantum information processing tasks like quantum cryptography, dense coding, quantum teleportation etc. have been shown to have advantages over their classical counterparts and have also been successfully implemented in laboratories.

Seminar featuring Titas Chanda, Harish-Chandra Research Institute

Emergence of quantum information science has led to a paradigm shift in communication systems. In the past couple of decades, quantum information processing tasks like quantum cryptography, dense coding, quantum teleportation etc. have been shown to have advantages over their classical counterparts and have also been successfully implemented in laboratories.

Hao Qin, Telecom ParisTech

We report a quantum hacking strategy on a Continuous-Variable (CV) Quantum Key Distribution (QKD) system by inserting an external light. In the implementations of CV QKD systems, transmitting openly local oscillator pulses is a potential vulnerability for an eavesdropper to launch side channel attacks. In this work, other than targeting on local oscillator, we concern two imperfections in a balanced homodyne detector used in CV QKD system: the imbalance in the beam splitter and the finite linear detection limit.