Recently, the research group of Faxian Xiu in the department of physics at Fudan University has firstly observed a novel field-induced spin density wave state in studying the electrical transport properties of Dirac semimetal ZrTe5 under high magnetic field, which offers a new perspective and ideas for the research of Dirac semimetals. The related article titled “Zeeman splitting and dynamical mass generation in Dirac semimetal ZrTe5”was published in the internationally authoritative journal-Nature Communications in August 12th. Especially, doctoral students Yanwen Liu and Xiang Yuan are respectively the first and second author, and professor Xiu is the corresponding author.

In recent years, Dirac semimetal has attracted considerable attentions. Dirac semimetal has similar band structure with graphite, which provides a good platform for researchers to do basic physics research and has broad application prospect due to its excellent electrical properties such as large magne to resistance and high electron mobility. Recently, a large number of theoretical studies have pointed out, the many-body correlation effects could induce novel phase transitions in Dirac semimetals and a Dirac mass is spontaneously generated by interaction effects, which had not been verified by experimental reports.

In this work, the research group of Faxian Xiu has studied the magne to transport properties of Dirac semimetal ZrTe5 under pulsed high magnetic field. The research has unveiled good quasi-2D nature of ZrTe5 behaving body-state quantum Hall effect. Meanwhile, the Zeeman splitting could be easily observed and this material can be driven into its quantum limit regime in a relatively weak magnetic field, leading to much more pronounced many-body correlation effects with increasing magnetic field. In an ultra-high magnetic field up to 60 T, an abnormal change of the resistance is observed in the sample, suggesting a field-induced phase transition, which is the spin density wave caused by the increasing many-body correlation effects after the system was driven into the quantum limit. This discovery indicates that Dirac semimetal is an ideal platform for investigating topological correlation effects, and provides a new research avenue for further studying of Dirac electronic properties.

Pulsed high magnetic field measurements were performed at Wuhan National High Magnetic Field Center. Prof. Xing Wu of East China Normal University and Prof. Jin Zou of University of Queensland in Australia provided the help of transmission electron microscope characterization; Theoretical support was provided by Prof. Zhong Wang of  Tsinghua University and Prof. Stefano Sanvito of Trinity College, Dublin, Ireland. This work was supported by the department of Physics and State Key Laboratory of Surface Physics of Fudan University, the National Young 1000 Talent Plan and National Natural Science Foundation of China.