Free space continuous variable Quantum Key Distribution with discrete phases
Anju Rani,
Pooja Chandravanshi,
Jayanth Ramakrishnan,
Pravin Vaity,
P. Madhusudhan,
Tanya Sharma,
Pranav Bhardwaj,
Ayan Biswas,
R.P. Singh
Affiliations
Anju Rani
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India; Indian Institute of Technology, Gandhinagar, 382355, India; Corresponding author at: Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India.
Pooja Chandravanshi
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India
Jayanth Ramakrishnan
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India
Pravin Vaity
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India
P. Madhusudhan
Femtosecond Laser Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India
Tanya Sharma
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India; Indian Institute of Technology, Gandhinagar, 382355, India
Pranav Bhardwaj
Femtosecond Laser Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India; Indian Institute of Technology, Gandhinagar, 382355, India
Ayan Biswas
York Centre for Quantum Technologies, University of York, United Kingdom
R.P. Singh
Quantum Science and Technology Laboratory, Physical Research Laboratory, Ahmedabad, 380009, India
Quantum Key Distribution (QKD) offers unconditional security in principle. Many QKD protocols have been proposed and demonstrated to ensure secure communication between two authenticated users. Continuous variable (CV) QKD offers many advantages over discrete variable (DV) QKD since it is cost-effective, compatible with current classical communication technologies, efficient even in daylight, and gives a higher secure key rate. Keeping this in view, we demonstrate a discrete modulated CVQKD protocol in the free space which is robust against polarization drift. We also present the simulation results with a noise model to account for the channel noise and the effects of various parameter changes on the secure key rate. These simulation results help us to verify the experimental values obtained for the implemented CVQKD.
