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arXiv · 2302.08821

Quantum-interference origin and magnitude of 1/$f$ noise in Dirac nodal line IrO$_2$ nanowires at low temperatures

Po-Yu Chien·Chih-Yuan Wu·Ruey-Tay Wang·Shao-Pin Chiu·Stefan Kirchner·Sheng-Shiuan Yeh·Juhn-Jong Lin
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Abstract

We present 1/$f$ noise measurements of IrO$_2$ nanowires from 1.7 to 350 K. Results reveal that the noise magnitude (represented by Hooge parameter $\gamma$) increases at low temperatures, indicating low-frequency resistance noise from universal conductance fluctuations. The cause of this noise is determined to be due to oxygen vacancies in the rutile structure of IrO$_2$. Additionally, the number density of these mobile defects can be calculated from the $\sqrt{T}$ resistance rise caused by the orbital two-channel Kondo effect in the Dirac nodal line metal IrO$_2$.

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Po-Yu Chien, Chih-Yuan Wu, Ruey-Tay Wang, Shao-Pin Chiu, Stefan Kirchner, Sheng-Shiuan Yeh, Juhn-Jong Lin. 2023-02-17. Quantum-interference origin and magnitude of 1/$f$ noise in Dirac nodal line IrO$_2$ nanowires at low temperatures. https://doi.org/10.1063/5.0147131

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