Correlated Oxide Dirac Semimetal in the Extreme Quantum Limit
cond-mat.str-el
/ Authors
Jong Mok Ok, Narayan Mohanta, Jie Zhang, Sangmoon Yoon, Satoshi Okamoto, Eun Sang Choi, Hua Zhou, Megan Briggeman, Patrick Irvin, Andrew R. Lupini
and 10 more authors
Yun-Yi Pai, Elizabeth Skoropata, Changhee Sohn, Haoxiang Li, Hu Miao, Benjamin Lawrie, Woo Seok Choi, Gyula Eres, Jeremy Levy, Ho Nyung Lee
/ Abstract
Quantum materials (QMs) with strong correlation and non-trivial topology are indispensable to next-generation information and computing technologies. Exploitation of topological band structure is an ideal starting point to realize correlated topological QMs. Herein, we report that strain-induced symmetry modification in correlated oxide SrNbO3 thin films creates an emerging topological band structure. Dirac electrons in strained SrNbO3 films reveal ultra-high mobility (100,000 cm2/Vs), exceptionally small effective mass (0.04me), and non-zero Berry phase. More importantly, strained SrNbO3 films reach the extreme quantum limit, exhibiting a sign of fractional occupation of Landau levels and giant mass enhancement. Our results suggest that symmetry-modified SrNbO3 is a rare example of a correlated topological QM, in which strong correlation of Dirac electrons leads to the realization of fractional occupation of Landau levels.