  Oblivious transfer between two untrusting parties is an important primitive
in cryptography. There are different variants of oblivious transfer. In Rabin
oblivious transfer, the sender Alice holds a bit, and the receiver Bob either
obtains the bit, or obtains no information with probability $p_?$. Alice should
not know whether or not Bob obtained the bit. We examine a quantum Rabin
oblivious transfer protocol that uses two pure states. Investigating different
cheating scenarios for the sender and for the receiver, we determine optimal
cheating probabilities in each case. Comparing the quantum Rabin oblivious
transfer protocol to classical Rabin oblivious transfer protocols, we show that
the quantum protocol outperforms classical protocols which do not use a third
party, for some values of $p_?$.
