Research directions

Fundamental Quantum Physics and Quantum Dynamics

Quantum systems demonstrate fascinating features that are absent in classical phenomena. We are exploring novel concepts in quantum physics and quantum dynamics both theoretically and experimentally. The research allows us not only to discover interesting quantum phase and quantum matter but also to develop versatile tools of quantum control for the implementation of quantum technologies.

Representative publications:

• 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, Experimental measurement of the quantum geometric tensor using coupled qubits in diamond, National Science Review, 7, 254 (2020). 

• Z.-J. Shu, Yu Liu, Qingyun Cao, Pengcheng Yang, Shaoliang Zhang, Martin B. Plenio, Fedor Jelezko, Jianming Cai, Observation of Floquet-Raman transition in a driven solid-state spin system, Phys. Rev. Lett. 121, 210501 (2018). 

• J.-M. Cai, Alex Retzker, Fedor Jelezko, Martin B. Plenio, A large-scale quantum simulator on diamond surface at room temperature, Nature Physics 9, 168-173 (2013).

Quantum Sensing and Quantum Measurement

Quantum sensing exploits the fundamental features of a quantum system to achieve a highly efficient measurement of physical quantities. We exploit fundamental quantum features (quantum superposition and quantum entanglement) to devise new strategies for quantum sensing and quantum measurement.

Representative publications:

• Yaoming Chu, S.-L. Zhang, B.-Y. Yu, and Jianming Cai, Dynamic Framework for Criticality-Enhanced Quantum Sensing, Phys. Rev. Lett. 126, 010502 (2021).

• Yaoming Chu, Yu Liu, Haibin Liu, Jianming Cai, Quantum sensing with a single-qubit pseudo-Hermitian system, Phys. Rev. Lett. 124, 020501 (2020).

• P.-C. Yang, M. Yu, R. Betzholz, C. Arenz, Jianming Cai, Complete quantum-state tomography with a local random field, Phys. Rev. Lett. 124, 010405 (2020). 

• Yu Liu, Jiazhao Tian, Ralf Betzholz, Jianming Cai, Pulsed quantum-state reconstruction of dark systems, Phys. Rev. Lett. 122, 110406 (2019).

• I. Baumgart, J.-M. Cai, A. Retzker, M. B. Plenio, Ch. Wunderlich, Ultrasensitive magnetometer using a single atom, Phys. Rev. Lett. 116, 240801 (2016)

Solid-State Quantum Sensing and Applications

The solid-state quantum system represents a promising candidate for the implementation of quantum sensing. Based on the solid-state spin system (e.g. NV center in diamond), we focus on the construction of novel quantum sensors for the precise measurement of the magnetic field, electric field and temperature; and explore the wide applications in the interdisciplinary fields.

Representative publications:

• 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, J.-M. Cai, Protecting quantum spin coherence of nanodiamonds in living cells, Phys. Rev. Applied 13, 024021 (2020). 

• Haibin Liu, M. B. Plenio, Jianming Cai, Scheme for detection of single-molecule radical pair reaction using spin in diamond, Phys. Rev. Lett. 118, 200402 (2017).  

• J.-M. Cai, F. Jelezko, M. B. Plenio, Hybrid sensors based on color centers in diamond and piezoactive layer, Nature Communications 5, 4065 (2014).       

• C. Müller, X. Kong, J.-M. Cai, K. Melentijevic , A. Stacey, M. Markham, D. Twitchen, J. Isoya, S. Pezzagna, J. Meijer, J.-F. Du , M. Plenio, B. Naydenov, L. P. McGuinness F. Jelezko, Nuclear magnetic resonance spectroscopy and imaging with single spin sensitivity. Nature Communications 5, 4703 (2014).

• A. Ermakova, G. Pramanik, J.-M. Cai, G. Algara-Siller, U. Kaiser, T. Weil, Y.-K. Tzeng , H. C. Chang , L. P. McGuinness, M. B. Plenio, B. Naydenov, and F. Jelezko, Detection of a Few Metallo-Protein Molecules Using Color Centers in Nanodiamonds, Nano Lett. 13 (7), 3305-3309 (2013).