Entanglement concentration of unknown states on separate nitrogen-vacancy centers via error-detected entanglement swapping

Abstract

Here we propose a new entanglement concentration protocol (ECP) for unknown lessentangled states on separate nitrogen-vacancy (NV) centers. The protocol exploits the errordetected entanglement swapping based on cavity quantum electrodynamics, which is more robust and practical than previous ECPs for NV centers. We present in detail the principle and the advantages of the ECP. Also, the performance of the protocol with current experimental parameters is discussed. We believe that the ECP could provide a promising building block for solid-state quantum repeaters and quantum networks in the future.

Heralded teleportation of a controlled-NOT gate for nitrogen-vacancy centers coupled to a microtoroid resonator

“…In 2016, another scheme was proposed for 'error-detected' generating and complete analysing of hyperentangled Bell states based on quantum dot (QD)-doublesided cavities [26]. Subsequently, several 'error-rejecting' QIP schemes are proposed [27][28][29][30][31][32][33], in which computational errors are mapped into heralded photon detections, which is a highly desirable feature for quantum communication or computation. Recently, Cao et al [33] proposed an entanglement concentration protocol for unknown less entangled states on separate nitrogen-vacancy (NV) centers exploits the 'error-detected' entanglement swapping.…”

“…Subsequently, several 'error-rejecting' QIP schemes are proposed [27][28][29][30][31][32][33], in which computational errors are mapped into heralded photon detections, which is a highly desirable feature for quantum communication or computation. Recently, Cao et al [33] proposed an entanglement concentration protocol for unknown less entangled states on separate nitrogen-vacancy (NV) centers exploits the 'error-detected' entanglement swapping. In 2017, another scheme for entanglement swapping and entanglement purification based on the scattering of photons off single emitters in one-dimensional waveguides was proposed [32].…”

“…is coupled. As described above, the photon would be reflected by the NV-MTR system, or be reflected by the MTR directly due to the mismatching between the incident photon and the WGM [24,33,62]. Then the state of the system composed of the NV center and the photon evolves to the unnormalized state…”

Compact entanglement concentration for three-electron-spin W states with error-detected parity-check gates

“…Since the first ECP with the Schmidt projection was proposed by Bennett et al [47], some practical and interesting ECPs [48][49][50][51][52][53][54] have been presented for photon systems with different methods, including linear-optics-based ECPs [48][49][50], an efficient cross-Kerr-nonlinearities-based ECP [51], photon-assisted ECPs [52,53], and hyperentanglementassisted ECP [54]. Besides, some deterministic ECPs with far higher efficient by iteration of the entanglement concentration process were proposed, such as atomic systems [55], quantum-dot (QD) electron-spin systems [56][57][58], and nitrogen-vacancy-center systems [59][60][61] have been proposed. Moreover, the efficiency of cross-Kerr-nonlinearities-based ECP [51] can also be increased by iteration of the entanglement concentration process.…”

Error-detected single-photon quantum routing using a quantum dot and a double-sided microcavity system

“…In 2016, another proposal for errordetected generating and complete analysing of hyperentangled Bell states with quantum dot (QD)-double-sided system was proposed. [54] Subsequently, several error-rejecting schemes for quantum repeaters, [55][56][57][58][59][60] quantum logic gates, [61][62][63][64][65] and entanglement generation [66] have been proposed, in which computational errors are heralded by single photon detections, resulting a unity operation fidelity, which is a highly desirable feature for quantum communication or computation.…”