Abstract:
Quantum key distribution (QKD) is a growing phenomenon rapidly being adopted
around the world because it adds unconditional security to our day to day communication.
Recent trend in QKD has shifted towards using continuous variables (CV)
to encode quantum data because of the ease in producing, manipulating, transmitting
and measuring these signals. In this thesis we have developed the foundation of
CV QKD with a generalized approach. By generalizing steps involved in CV QKD
protocols, we have simulated several Gaussian as well as non-Gaussian protocols
enabling us to quickly explore improvement opportunities in any CV QKD protocol.
Resultingly we were able to find significant improvement in measurement device
independent (MDI) protocol. Our method allows the generation of a positive key
rate when initial squeezing is low, additionally these states offer more tolerance to
thermal noise. Such states bring MDI protocol closer to commercial realization.
