91 citations · 179 across the 17 of their papers we have counts for
19 papers · 1 filter
Combining Error Verification and Privacy Amplification in Quantum Key Distribution
Devashish Tupkary, Zhiyao Wang, Ernest Y. -Z. Tan
Quantum Key Distribution (QKD) protocols typically involve two separate steps of error-verification and privacy amplification. Both steps involve the application of a hash function…
Security framework for practical quantum key distribution with imperfect devices
Jerome Wiesemann, John Burniston, Devashish Tupkary +1
Practical quantum key distribution (QKD) systems inevitably exhibit imperfections in both the source and detector. At the same time, the behavior of these imperfect devices is neve…
Experimental quantum cryptography with single photons and imperfect devices
Aodhán Corrigan, Koray Kaymazlar, Zhiyao Wang +9
Quantum key distribution (QKD) allows for provably secure key distribution between two trusted parties. Because the security and performance of QKD protocols rely on devices that b…
Rigorous Security Proofs for Practical Quantum Key Distribution
Devashish Tupkary
This thesis is concerned with rigorous security analyses of practical Quantum Key Distribution (QKD) protocols, using a variety of modern proof techniques. The main results are as…
Semidefinite programming for understanding the limitations of Lindblad equations
Soumyadeep Sarma, Manas Kulkarni, Archak Purkayastha +1
Lindbladian quantum master equations (LEs) are the most popular descriptions for quantum systems weakly coupled to baths. But, recent works have established that in many situations…
A rigorous and complete security proof of decoy-state BB84 quantum key distribution
Devashish Tupkary, Shlok Nahar, Amir Arqand +2
We present a rigorous and complete security proof of the decoy-state BB84 quantum key distribution (QKD) protocol. Our analysis aims to achieve a high standard of mathematical rigo…
Authentication in Security Proofs for Quantum Key Distribution
Devashish Tupkary, Shlok Nahar, Ernest Y. -Z. Tan
Quantum Key Distribution (QKD) protocols rely on authenticated classical communication. Typical QKD security proofs are carried out in an idealized setting where authentication is…
Phase error estimation for passive detection setups with imperfections and memory effects
Zhiyao Wang, Devashish Tupkary, Shlok Nahar
We develop a generic framework to bound the phase error rate for quantum key distribution protocols using passive detection setups with imperfections and memory effects. This frame…
Security of quantum key distribution with source and detector imperfections through phase-error estimation
Guillermo Currás-Lorenzo, Margarida Pereira, Shlok Nahar +1
Quantum key distribution promises information-theoretic security, but practical implementations face vulnerabilities due to device imperfections. Existing security proofs typically…
Imperfect detectors for adversarial tasks with applications to quantum key distribution
Shlok Nahar, Devashish Tupkary, Norbert Lütkenhaus
Security analyses in quantum key distribution (QKD) and other adversarial quantum tasks often assume perfect device models. However, real-world implementations often deviate from t…
Improved finite-size effects in QKD protocols with applications to decoy-state QKD
Lars Kamin, Devashish Tupkary, Norbert Lütkenhaus
We present a finite-size security proof for generic quantum key distribution protocols against independent and identically distributed collective attacks and extend it to coherent…
Security proofs for practical QKD: variations, techniques, gaps, and limitations
Devashish Tupkary, Ernest Y. -Z. Tan, Shlok Nahar +2
We review the current status of security proofs for practical decoy-state Quantum Key Distribution using the BB84 protocol, focusing on optical implementations with weak coherent p…
Phase error rate estimation in QKD with imperfect detectors
Devashish Tupkary, Shlok Nahar, Pulkit Sinha +1
We present a finite-size security proof of the decoy-state BB84 QKD protocol against coherent attacks, using entropic uncertainty relations, for imperfect detectors. We apply this…
A consolidated and accessible security proof for finite-size decoy-state quantum key distribution
Jerome Wiesemann, Jan Krause, Devashish Tupkary +3
In recent years, quantum key distribution (QKD) has evolved from a scientific research field to a commercially available security solution, supported by mathematically formulated s…
Postselection technique for optical Quantum Key Distribution with improved de Finetti reductions
Shlok Nahar, Devashish Tupkary, Yuming Zhao +2
The postselection technique is an important proof technique for proving the security of quantum key distribution protocols against coherent attacks. In this work, we go through mul…
Security Proof for Variable-Length Quantum Key Distribution
Devashish Tupkary, Ernest Y. -Z. Tan, Norbert Lütkenhaus
We present a security proof for variable-length QKD in the Renner framework against IID collective attacks. Our proof can be lifted to coherent attacks using the postselection tech…
Using Cascade in Quantum Key Distribution
Devashish Tupkary, Norbert Lütkenhaus
We point out a critical flaw in the analysis of Quantum Key Distribution (QKD) protocols that employ the two-way error correction protocol Cascade. Specifically, this flaw stems fr…
Searching for Lindbladians obeying local conservation laws and showing thermalization
Devashish Tupkary, Abhishek Dhar, Manas Kulkarni +1
We investigate the possibility of a Markovian quantum master equation (QME) that consistently describes a finite-dimensional system, a part of which is weakly coupled to a thermal…
Fundamental limitations in Lindblad descriptions of systems weakly coupled to baths
Devashish Tupkary, Abhishek Dhar, Manas Kulkarni +1
It is very common in the literature to write down a Markovian quantum master equation in Lindblad form to describe a system with multiple degrees of freedom and weakly connected to…