One-out-of-two Quantum Oblivious Transfer based on Nonorthogonal States

TL;DR

This paper introduces a new one-out-of-two quantum oblivious transfer protocol using nonorthogonal states, which enhances security against cheating and is more efficient than existing methods, without falling under known no-go theorems.

Contribution

It presents a novel quantum oblivious transfer protocol based on nonorthogonal states that is secure, efficient, and directly utilizes quantum resources without relying on classical key structures.

Findings

Protocol is secure against external and internal attacks.

It prevents entangled cheating by illegal agents.

It is more efficient than existing two-level structure protocols.

Abstract

This study proposes a simple and efficient one-out-of-two quantum oblivious transfer (QOT) protocol based on nonorthogonal states. The nonorthogonal property grants quantum bit immunity to some operations in order to achieve the irreversible goal of discarding a message, resulting in a one-out-of-two selection effect. In addition, it can also prevent entangled cheating from an illegal agent. The resulting QOT protocol is therefore built directly on quantum resources, rather than on a two-level structure which must first create two classical keys using the quantum resources (all-or-nothing QOT), and then build the one-out-of-two protocol from there. Furthermore, the proposed protocol allows Alice to test Bob's loyalty by comparing the measurement results. Moreover, the relationship with the no-go theorem is discussed in detail; this relationship is often overlooked in other studies. The no-go theorem discussion and security analysis demonstrate that the proposed protocol does not belong to the no-go theorem constraint, and is secure against both external and internal attacks. In addition, the efficacy analysis shows that the proposed protocol is more efficient than other two-level structure protocols.