Hyperparallel quantum information processing outperforms its traditional parallel one in terms of channel capacity, low loss rate, and processing speed. We present a way for implementing a robust hyper-parallel optical controlled-phase-flip gate through microcavities. The gate acts on polarization and spatial degrees of freedom (DOFs) simultaneously, and the incomplete and undesired interactions between photons and quantum dots are prevented. Interestingly, the unity fidelity of the gate can be achieved in principle, and the success of the gate is heralded by the single-photon detectors.

Hyperentangled states can outperform their classical counterparts on solving certain tasks. Here, a simplified scheme for completely distinguishing two-photon hyperentangled Bell states in polarization, spatial, and time-bin degrees of freedom (DOFs) is presented. Unity fidelity can be achieved in principle without strong couple limitation between photon and quantum dot (QD), and the incomplete and imperfect QD-cavity interactions are prevented by single-photon detectors. In addition, auxiliary photons or DOFs are not required in the scheme. The necessary linear optical elements are fewer than the parity-check-based one.

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