Personal Biography

Junqiu Liu is a principal investigator at Shenzhen International Quantum Academy and a tenure-track assistant professor at Hefei National Laboratory, University of Science and Technology of China (USTC). He received Ph.D. from EPFL in 2020, MSc (with highest distinction) from FAU Erlangen-Nuremberg in 2016, and BSc from USTC in 2012. His research lies in the interdisciplinary domains of integrated photonics, nonlinear optics, quantum information, MEMS, and microwave photonics. His PhD thesis entitled “Silicon Nitride Integrated Nonlinear Photonics” was awarded 2021 EPFL Doctorate Award, “For ground breaking experiments in the field of chip-scale frequency combs and the extraordinary record of scientific accomplishments”. Till 2025 he has published more than 90 publications, including 7 Nature, 3 Science, 5 Nature Photonics, 2 Nature Physics, 18 Nature Communications, 4 Science Advances, 4 Light: Science & Applications, 3 PRL, 2 PRX, 5 Optica etc. He has been awarded with the 2025 European Physical Society (EPS) Fresnel Prize, “For pioneering contributions to ultralow-loss silicon nitride integrated photonics and its applications in nonlinear optics, quantum information, and frequency metrology, bridging fundamental and applied physics”. His research has seeded several startups. He has being serving as an associate editor at Physical Review Applied since 2024.

Education Background

l 07.2016 – 07.2020: Doctoral Program on Photonics at École Polytechnique Fédérale de Lausanne (EPFL), Switzerland. Advisor: Prof. Tobias J. Kippenberg.

PhD thesis title: Silicon Nitride Integrated Nonlinear Photonics. Thesis defense jury: Prof. Kerry Vahala, Prof. John E. Bowers, Prof. Camille-Sophie Brès, and Prof. Luc Thévenaz.

I am a recipient of the EPFL Doctorate Award, “For ground breaking experiments in the field of chip-scale frequency combs and the extraordinary record of scientific accomplishments”. This award is the highest honour and for the best two PhD theses submitted from all EPFL schools in year 2020-2021.

l 10.2013 – 05.2016: Master Program in Advanced Optical Technologies, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Germany.

Final grade: 1.1/1.0 (rank 1st in the department, top 1% among all university graduates), “mit Auszeichnung bestanden (with highest distinction)”. Master of Science with Honours received.

l 09.2008 – 06.2012: Undergraduate study at School for the Gifted Young (少年班), University of Science and Technology of China (USTC). Major in Physics. Bachelor of Science received.

Working Experience

l Since 01.2022: Tenure-track assistant professor at Hefei National Laboratory, USTC.

l Since 01.2022: Principal research fellow at Shenzhen International Quantum Academy.

l 08.2020 – 12.2021: Postdoc at EPFL. Advisor: Prof. Tobias J. Kippenberg.

Selected Publications

1. D. Chen, Z. Zhong, S. Huang, J. Sun, S. Zeng, B. Shi, Y.-H. Luo, and J. Liu^#. Light coupling to photonic integrated circuits using optimized lensed fibers. Phys. Rev. Applied (2026).

2. S. Li, K. Yu, D. A. Chermoshentsev, W. Sun^#, J. Long, X. Yan, C. Shen, A. E. Shitikov, N. Y. Dmitriev, I. A. Bilenko, and J. Liu^#. Universal Kerr-thermal dynamics of self-injection-locked microresonator dark pulses. Phys. Rev. Lett. 135, 133803 (2025).

3. B. Shi, M.-Y. Zheng, Y. Hu, Y. Zhao, Z. Shang, Z. Chen, Y.-H. Luo, J. Long, W. Sun, W. Ma, X.-P. Xie, L. Gao, C. Shen, A. Wang, W. Liang, Q. Zhang, and J. Liu^#. A hyperfine-transition-referenced vector spectrum analyzer for visible-light integrated photonics. Nature Communications 16, 7025 (2025).

4. J. Long, Z. Wang, H. Peng, W. Sun, D. Chen, S. Li, S. Li, Y.-H. Luo, J. He, L. Gao, B. Shi, C. Shen, L. Li, T. Long, B. Chen, Z. Li, and J. Liu^#. A chip-based optoelectronic-oscillator frequency comb. eLight 5, 14 (2025).

5. S. Li, W. Luo, Z. Li^#, and J. Liu^#. High-speed Mach-Zehnder modulators based on nonlinear optics and complex band structures. Phys. Rev. Applied 24, 014021 (2025).

6. W. Sun, Z. Chen, L. Li, C. Shen, K. Yu, S. Li, J. Long, H. Zheng, L. Wang, T. Long, Q. Chen, Z. Zhang, B. Shi, L. Gao, Y.-H. Luo, B. Chen^#, and J. Liu^#. A chip-integrated comb-based microwave oscillator. Light: Science & Applications 14, 179 (2025).  

7. R. Chen, Y.-H. Luo, J. Long, and J. Liu. Arbitrary-phase locking of fiber unbalanced Mach-Zehnder interferometers. Phys. Rev. Applied, 22, 054051 (2024).

8. H. Tian, J. Liu et al. Piezoelectric actuation for integrated photonics. Adv. Opt. Photon. 16, 749 (2024).

9. R. Chen, Y.-H. Luo^#, J. Long, B. Shi, C. Shen, and J. Liu^#. Ultralow-loss integrated photonics enables bright narrow-band photon-pair sources. Phys. Rev. Lett. 133, 083803 (2024).

10. Y.-H. Luo, B. Shi, W. Sun, R. Chen, S. Huang, Z. Wang, J. Long, C. Shen, Z. Ye, H. Guo, and J. Liu^#. A wideband, high-resolution vector spectrum analyzer for integrated photonics.  Light: Science & Applications 13, 83 (2024).

11. B. Shi, Y.-H. Luo, W. Sun, Y. Hu, J. Long, X. Bai, A. Wang, and J. Liu^#. Frequency-comb-linearized, widely tunable lasers for coherent ranging. Photonics Research 12, 664 (2024).

12. H.  Zheng, W. Sun^#, H. Wen, X. Ding, R. Chen, B. Shi, Y.-H. Luo, J. Long, C. Shen, S. Meng, H. Guo, and J. Liu^#. Programmable access to microresonator solitons with modulational sideband heating. APL Photonics 8, 126110 (2023).

13. Z. Ye, H. Jia, Z. Huang, C. Shen, J. Long, B. Shi, Y.-H. Luo, L. Gao, W. Sun, H. Guo, J. He, and J. Liu^#. Foundry manufacturing of tight-confinement dispersion-engineered ultralow-loss silicon nitride photonic integrated circuit. Photonics Research 11, 558 (2023).

14. N. M. Kondratiev et al. Recent advances in laser self-injection locking to high-Q microresonators. Front. Phys. 18, 21305 (2023).

15. X. Ji, J. Liu^#, J. He, R. N. Wang, J. Riemensberger, and T. J. Kippenberg^#. Compact, spatial-mode-interaction-free, ultralow-loss, nonlinear photonic integrated circuits. Communications Physics 5, 84 (2022).

16. J. Liu et al. High-yield, wafer-scale fabrication of ultralow-loss, dispersion-engineered silicon nitride photonic circuits. Nature Communications 12, 2236 (2021).

17. C. Xiang*, J. Liu* et al. Laser soliton microcombs heterogeneously integrated on silicon. Science 373, 99 (2021).

18. H. Tian*, J. Liu*, A. Siddharth, R. N. Wang, T. Blésin, J. He. T. J. Kippenberg, and S. A. Bhave. Magnetic-free silicon nitride integrated optical isolator. Nature Photonics 15, 828 (2021).

19. J. Liu et al. Monolithic piezoelectric control of soliton microcombs. Nature 583, 385 (2020).

20. J. Liu et al. Photonic microwave generation in the X- and K-band using integrated soliton microcombs. Nature Photonics 14, 486 (2020).

21. B. Shen*, L. Chang*, J. Liu*, H. Wang*, Q.-F. Yang* et al. Integrated turnkey soliton microcombs. Nature 582, 365 (2020).

22. F. Gyger*, J. Liu*, F. Yang* et al. Observation of stimulated Brillouin scattering in silicon nitride integrated waveguides. Phys. Rev. Lett. 124, 013902 (2020).

23. J. Liu et al. Ultralow-power chip-based soliton frequency combs for photonic integration. Optica 5, 1347 (2018).

24. J. Liu et al. Double inverse nanotapers for efficient light coupling to integrated photonic devices. Optics Letters 43, 3200 (2018).

25. M. H. Pfeiffer*, J. Liu*, M. Geiselmann, and T. J. Kippenberg. Coupling ideality of integrated planar high-Q microresonators. Phys. Rev. Applied 7, 024026 (2017).

26. J. Liu et al. Frequency-comb-assisted broadband precision spectroscopy with cascaded diode lasers. Optics Letters 41, 3134 (2016).

Full list of publication is found in Google Scholar link

https://scholar.google.com/citations?hl=en&user=s2uQynQAAAAJ&view_op=list_works&sortby=pubdate

Honors and Awards

· Fresnel Prize, awarded by European Physical Society (EPS) Quantum Electronics and Optics Division, 2025.

· PhotoniX Prize for Technological Breakthrough, 2023.

· EPFL Doctorate Award, awarded by EPFL to the best two PhD theses among all schools, 2021.

· 35 Innovators Under 35 (China List), awarded by MIT Technology Review, 2020.

· Rising Stars of Light, awarded by Light: Science & Applications, 2020.

· Chinese government award for outstanding self-finance students abroad, 2020.

· Finalist of Best Student Paper Award in the Joint Conference of the IEEE IFCS-ISAF, 2020.

· ECIO 2019 the Best Student Paper, awarded by Nature Photonics and UGhent-IMEC, 2019.

· IFCS-EFTF 2019 student travel grant, 2019.