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arXiv · 1205.3045

Quantum Oscillations in the High Pressure Metallic State of Ca$_2$RuO$_4$

Swee K. Goh·P. L. Alireza·Lina E. Klintberg·T. Murphy·F. Nakamura·David J. Singh·Mike Sutherland
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Abstract

We present evidence for quantum oscillations in the pressure-induced metallic state of the 4$d$ layered perovskite Ca$_2$RuO$_4$. A complicated oscillation spectrum is observed, which is both temperature and field dependent, with unusually light cyclotron masses in the range of $m^*/m_e$ $\sim$ 0.6 -- 3, suggesting that the pressure-induced metallic state is a weakly correlated Fermi liquid. We compare our observations to band structure calculations within the local spin density approximation, and conclude that some features of the spectrum are a result of non-linear spin splitting effects.

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Swee K. Goh, P. L. Alireza, Lina E. Klintberg, T. Murphy, F. Nakamura, David J. Singh, Mike Sutherland. 2012-05-14. Quantum Oscillations in the High Pressure Metallic State of Ca$_2$RuO$_4$. https://arxiv.org/abs/1205.3045

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