Institute: Indian Institute of Technology (IIT), Kanpur

Principal Investigator: Dr. K. Pradeep Kumar

Co-Principal Investigator: Dr. Rohit Budhiraja

The aim of the project is to develop a single-carrier decoy-state frequency-coded quantum key distribution (QKD) system and demonstrate key exchange over 50 km optical fiber link. A second objective of the proposal is to develop a high-speed true random number generator (TRNG) based on large bandwidth optical chaos in erbium-doped fiber lasers. The twin aims of the proposal are interrelated to each other since QKD requires a reliable source of randomness which will be provided by the TRNG.

In this project, We intend to deliver the following:

• Fully operational node-to-node single-carrier frequency-coded quantum key distribution (QKD) system over fiber-optic channel with following specifications: Raw key rate = 1 Mbps, Span length ≥ 50 km, Single-photon detector modules with dark count rate ≤ 10-5 per pulse, Three-level decoy-state method to enhance key rate.
• Develop single-photon detector modules using commercial APD-TIAs at 1550 nm (C-band) with dark count rate ≤ 10-5 per pulse, resolution time of 3 ns, repetition rate of 1 MHz or better.
• Develop 2.4 GHz and 4.8 GHz RF transmitter and receiver boards using commercial ICs and FPGAs with on board clock recovery modules for carrier synchronization.
• True random number generator (TRNG) based on optical chaos in fiber lasers with real-time random number generation rate of 10 Mbps or better. An additional deliverable using TRNG device is bank of random numbers which have successfully passed NIST and DIEHARD test suites for use in QKD.
• FPGA based digital transceivers for key reconciliation, privacy amplification, and final key generation.