Leader of the Nuclear Theory Group
Division of Theoretical Physics
School of Physics and Astronomy
Sun Yat-sen University, China
Office B318, BLD Hanlin
Sun Yat-sen University
Tangjiawan, Xiangzhou District
Zhuhai City, Guangdong Province, China
Post Code: 519082
中国广东省珠海市香洲区唐家湾
中山大学珠海校区翰林楼B318
邮编：519082
personal page @ SPA, SYSU
Developing a Novel Ab Initio Nuclear Theory Framework: Yao et al. have innovatively combined the in-medium similarity renormalization group (IMSRG) with the quantum-number projected generator coordinate method (PGCM) to develop the in-medium generator coordinate method (IM-GCM) [PRL 124, 232501 (2020)]. This method overcomes the limitations of ab initio approaches in studying deformed nuclei and has, for the first time, enabled ab initio calculations of nuclear matrix elements for neutrinoless double-beta decay candidate nuclei, laying the foundation for achieving high-precision nuclear matrix elements. Furthermore, based on the IM-GCM approach, Yao et al., from first principles, unveiled the microscopic mechanism underlying the emergence of strong collective deformation in the ground states of “island of inversion” nuclei, offering a new perspective for understanding nuclear structure phenomena [arXiv:2410.23113].
Advancing the Precise Calculation of Nuclear Matrix Elements for Neutrinoless Double-Beta Decay: Neutrinoless double-beta decay provides one of the most effective probes for testing whether neutrinos are Majorana particles and for exploring new physics beyond the Standard Model. The precise calculation of its nuclear matrix elements (NMEs) is crucial for guiding experimental design and constraining the neutrino mass. Based on nuclear forces derived from chiral effective field theory and weak decay operators within the standard decay mechanism, Yao et al., for the first time, quantified the significant (~43%) enhancement of NMEs due to the leading-order short-range transition operator [PRL 127, 242502 (2021)]. The convergence of NMEs with respect to the chiral expansion order was systematically tested in candidate nuclei. Furthermore, leveraging machine learning techniques and statistical methods, Yao et al. have computed the NME for the key candidate nucleus 76Ge, providing a comprehensive analysis of both systematic and statistical uncertainties [PRL 132, 182502 (2024)]. This research advances the precision of NME calculations for neutrinoless double-beta decay, offering valuable theoretical input for domestic and international detection experiments, including those at the Jinping Underground Laboratory.
Developing Multireference Covariant Density Functional Theory for Systematic Studies of Nuclear Structure and Decay: Based on relativistic covariant density functional theory (CDFT), Yao et al. have introduced quantum-number projection techniques to restore angular momentum and parity symmetries of nuclear wave functions. By incorporating the generator coordinate method (GCM) to account for shape mixing effects, they have developed a fully microscopic and self-consistent multireference covariant density functional theory (MR-CDFT), providing an advanced theoretical framework for systematic studies of nuclear structure and decay properties. Using MR-CDFT, Yao et al. has achieved significant breakthroughs in nuclear low-lying excitations and neutrinoless double-beta decay. These include revealing the microscopic mechanisms behind triaxial deformation in nuclear low-lying spectra [PRC 89, 054306 (2014)] and octupole correlations [PRC 92, 041304(R) (2015); PLB 753, 227 (2016)], quantifying for the first time the relativistic effects in nuclear matrix elements (NMEs) of neutrinoless double-beta decay [PRC 90, 054309 (2014) (Editors’ Suggestion); PRC 91, 024316 (2015)], and identifying the leading-order contributions of nonstandard decay mechanisms [PLB 856, 138896 (2024)]. Recently, Yao et al. extended MR-CDFT to describe low-lying states in odd-mass nuclei [PRC 109, 034305 (2024)] and, through the eigenvector continuation (EC) method, proposed the subspace-projected multireference covariant density functional theory (SP-CDFT). This approach has uncovered correlations between NMEs of neutrinoless double-beta decay and nuclear low-lying states [arXiv:2408.00691] as well as heavy-ion collision fragmentation distributions [arXiv:2502.08027], offering alternative experimental strategies for indirectly constraining NMEs with higher precision.
A. Belley, J. M. Yao*, B. Bally, J. Pitcher, J. Engel, H. Hergert, J.D. Holt, T. Miyagi, T.R. Rodriguez, A.M. Romero, S.R. Stroberg, X. Zhang, Ab initio Uncertainty Quantification of Neutrinoless Double-Beta Decay in 76Ge, Phys. Rev. Lett. 132, 182502 (2024).
J. M. Yao, J. Meng, Y. F. Niu, P. Ring, Beyond-mean-field approaches for nuclear neutrinoless double beta decay in the standard mechanism, Prog. Part. Nucl. Phys. 126, 103965 (2022).
R. Wirth*, J. M. Yao*, H. Hergert*, "Ab initio calculation of the contact operator contribution in the standard mechanism for neutrinoless double beta decay", Phys. Rev. Lett. 127, 242502 (2021).
J. M. Yao, "Advances in modeling nuclear matrix elements of neutrinoless double beta decay", Science Bulletin, Volume 66, 3-5 (2021).
J. M. Yao, B. Bally, J. Engel, R. Wirth, T. R. Rodríguez, and H. Hergert, "Ab Initio Treatment of Collective Correlations and the Neutrinoless Double Beta Decay of 48Ca", Phys. Rev. Lett. 124, 232501 (2020).
J. M. Yao, E. F. Zhou, and Z. P. Li, "Beyond relativistic mean-field approach for nuclear octupole excitations", Phys. Rev. C 92, 041304(R) (2015).