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arXiv · 2108.08408

Correlated Oxide Dirac Semimetal in the Extreme Quantum Limit

Jong Mok Ok·Narayan Mohanta·Jie Zhang·Sangmoon Yoon·Satoshi Okamoto·Eun Sang Choi·Hua Zhou·Megan Briggeman·Patrick Irvin·Andrew R. Lupini·Yun-Yi Pai·Elizabeth Skoropata·Changhee Sohn·Haoxiang Li·Hu Miao·Benjamin Lawrie·Woo Seok Choi·Gyula Eres·Jeremy Levy·Ho Nyung Lee
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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.

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Jong Mok Ok, Narayan Mohanta, Jie Zhang, Sangmoon Yoon, Satoshi Okamoto, Eun Sang Choi, Hua Zhou, Megan Briggeman, Patrick Irvin, Andrew R. Lupini, Yun-Yi Pai, Elizabeth Skoropata, Changhee Sohn, Haoxiang Li, Hu Miao, Benjamin Lawrie, Woo Seok Choi, Gyula Eres, Jeremy Levy, Ho Nyung Lee. 2021-08-18. Correlated Oxide Dirac Semimetal in the Extreme Quantum Limit. https://doi.org/10.1126/sciadv.abf963

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