2020

Q.-Y. Cao, P.-C. Yang, M.-S. Gong, M. Yu, A. Retzker, M.B. Plenio, C. Müller, N. Tomek, B. Naydenov, L.P. McGuinness, F. Jelezko, and J.-M. Cai, Phys. Rev. Applied 13, 024021 (2020)

Here we demonstrate energy-efficient protection of N-V spin coherence in nanodiamonds using concatenated continuous dynamical decoupling, which exhibits excellent performance with a less-stringent microwave-power requirement.

Yaoming Chu, Yu Liu, Haibin Liu, and Jianming Cai, Phys. Rev. Lett. 124, 020501 (2020)

Here, we propose a strategy to realize a single-qubit pseudo-Hermitian sensor from a dilated two-qubit Hermitian system. The pseudo-Hermitian sensor exhibits divergent susceptibility in a dynamical evolution that does not necessarily involve an exceptional point.

Pengcheng Yang, Min Yu, Ralf Betzholz, Christian Arenz, and Jianming Cai, Phys. Rev. Lett. 124, 010405 (2020).

Beyond quantum-state tomography, we outline how this principle can be leveraged to characterize and control quantum processes in cases where the system model is not known.

Min Yu, Pengcheng Yang, Musang Gong, Qingyun Cao, Qiuyu Lu, Haibin Liu, Shaoliang Zhang, Martin B Plenio, Fedor Jelezko, Tomoki Ozawa, Nathan Goldman, Jianming Cai, National Science Review 7: 254-260, 2020.

Our results establish coherent dynamical responses as a versatile probe for quantum geometry, and they pave the way for the detection of novel topological phenomena in solid state.

Qianqian Chen, Haibin Liu, Min Yu, Shaoliang Zhang, and Jianming Cai, Phys. Rev. A 102, 052606 (2020)

We propose a dynamical decoupling scheme that sustains the topological phase transition overcoming the influence of dephasing. Therefore, the proposal would facilitate the observation of topological frequency conversion in the solid-state spin system, e.g., nitrogen-vacancy center in diamond.

Jiazhao Tian, Haibin Liu, Yu Liu, Pengcheng Yang, Ralf Betzholz, Ressa S. Said, Fedor Jelezko, and Jianming Cai, Phys. Rev. A 102, 043707 (2020)

Under environmental noise, an XY-8 sequence constituted by optimized gates prolongs the coherence time by 50% compared with standard rectangular pulses in our numerical simulations, showing the application potential of our phase-modulated method in improving the precision of signal detection in the field of quantum sensing.

Jiazhao Tian, Tianyi Du, Yu Liu, Haibin Liu, Fangzhou Jin, Ressa S. Said, and Jianming Cai, Phys. Rev. A 100, 012110 (2019)

Here, we adopt the strategy of optimal quantum control to accelerate coherent-state transfer in the ground-state manifold of the NV center spin using a laser. The results demonstrate improved performance in both the speed and the fidelity of coherent-state transfer which will be useful for optical control of the NV center spin in diamond.

Wanlu Song, Tianyi Du, Haibin Liu, Ralf Betzholz and Jianming Cai, New J. Phys. 22, 063029 (2020)

We propose a nanotube double quantum dot spin transducer that allows to achieve steady-state entanglement between nitrogen-vacancy center spins in diamond with spatial separations up to micrometers.

Qianqian Chen, Jianming Cai, and Shaoliang Zhang, Phys. Rev. A 101, 043614 (2020)

Our work provides a model based on ultracold atoms towards the implementation of versatile topological matters and topological phenomena in condensed matter systems.