Efficient Factorization with a Single Pure Qubit and logN Mixed Qubits
S. Parker, Martin Bodo Plenio · Physical Review Letters · 2000
It is commonly assumed that Shor's quantum algorithm for the efficient factorization of a large number N requires a pure initial state. Here we demonstrate that a single pure qubit, together with a collection of log 2N qubits in an arbitrary mixed state, is sufficient to implement Shor's factorization algorithm efficiently.