title: Parallel photonic quantum computation assisted by quantum dots in one-side optical microcavities.
abstract: Universal quantum logic gates are important elements for a quantum computer. In contrast to previous constructions on one degree of freedom (DOF) of quantum systems, we investigate the possibility of parallel quantum computations dependent on two DOFs of photon systems. We construct deterministic hyper-controlled-not (hyper-CNOT) gates operating on the spatial-mode and the polarization DOFs of two-photon or one-photon systems by exploring the giant optical circular birefringence induced by quantum-dot spins in one-sided optical microcavities. These hyper-CNOT gates show that the quantum states of two DOFs can be viewed as independent qubits without requiring auxiliary DOFs in theory. This result can reduce the quantum resources by half for quantum applications with large qubit systems, such as the quantum Shor algorithm.
authors.affiliation: 1] Information Security and National Computing Grid Laboratory, Southwest Jiaotong University, Chengdu 610031, China [2] State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China [3] State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences), Beijing 100049, China.
authors.forename: Ming-Xing
authors.initials: MX
authors.lastname: Luo
authors.affiliation: School of Electronic Engineering, Dublin City University, Dublin 9, Ireland.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wang