Continuous variable direct secure quantum communication using Gaussian states
This work addresses secure communication challenges in quantum cryptography, offering incremental improvements by simplifying state requirements and generalizing to various cryptographic tasks.
The authors tackled secure quantum communication by designing continuous variable schemes using Gaussian states, specifically proposing a quantum secure direct communication scheme and a controlled quantum dialogue scheme with single-mode squeezed coherent states, and proved their security against attacks like Gaussian quantum cloning and intercept resend, while eliminating the need for two-mode squeezed states.
Continuous variable one-way and controlled-two-way secure direct quantum communication schemes have been designed using Gaussian states. Specifically, a scheme for continuous variable quantum secure direct communication and another scheme for continuous variable controlled quantum dialogue are proposed using single-mode squeezed coherent states. The security of the proposed schemes against a set of attacks (e.g., Gaussian quantum cloning machine and intercept resend attacks) has been proved. Further, it is established that the proposed schemes do not require two-mode squeezed states which are essential for a set of existing proposals. The controlled two-way communication scheme is shown to be very general in nature as it can be reduced to schemes for various relatively simpler cryptographic tasks like controlled deterministic secure communication, quantum dialogue, quantum key distribution. In addition, it is briefly discussed that the proposed schemes can provide us tools to design quantum cryptographic solutions for several socioeconomic problems.