Singh, A. (ECE) – Quantum Key Distribution Using Entangled Pairs with Random Grouping

Quantum Key Distribution (QKD) provides information-theoretic security for cryptographic key establishment, but existing protocols exhibit limited noise tolerance, restricting their applicability in practical quantum channels with finite resources. This work introduces a QKD protocol based on entanglement swapping that significantly enhances error tolerance and key generation rates. The protocol encodes six-bit classical symbols into six-qubit entangled states organized as three Bell pairs. Key contributions include: (1) maintaining positive secrecy rates under 100% intercept-resend attacks, unprecedented among existing protocols, (2) proven security against collective attacks up to 29.29% quantum bit error rate (QBER), substantially exceeding BB84’s 11% threshold, and (3) finite-key security analysis demonstrating viable key generation under practical block size constraints. These results establish that structured multi-qubit encoding fundamentally broadens the operational capabilities of quantum key distribution, enabling secure communication in high-noise environments such as free-space satellite links and urban channels where conventional protocols fail.

Host: Archana Jayprakash Singh, Ph.D. Student, Electrical and Computer Engineering 

Advisor: Zouheir Rezki