Entangling power in deterministic quantum computation with one qubit
Chang‐shui Yu, X. X. Yi, He‐Shan Song, Heng Fan · Physical Review A · 2013
Deterministic quantum computing with one qubit (DQC1) is a mixed-state quantum computation algorithm that evaluates the normalized trace of a unitary matrix and is more powerful than the classical counterpart. We find that the normalized trace of the unitary matrix can be directly described by the entangling power of the quantum circuit of DQC1, so the nontrivial DQC1 is always accompanied by nonvanishing entangling power. In addition, it is shown that the entangling power also determines the intrinsic complexity of this quantum computation algorithm, i.e., larger entangling power corresponds to higher complexity. In addition, it is also shown that nonvanishing entangling power always exists in other similar tasks of DQC1.