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arXiv · 1711.05759

Angle-dependent electron spin resonance of YbRh$_2$Si$_2$ measured with planar microwave resonators and in-situ rotation

Linda Bondorf·Manfred Beutel·Markus Thiemann·Martin Dressel·Daniel Bothner·Jörg Sichelschmidt·Kristin Kliemt·Cornelius Krellner·Marc Scheffler
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Abstract

We present a new experimental approach to investigate the magnetic properties of the anisotropic heavy-fermion system YbRh$_2$Si$_2$ as a function of crystallographic orientation. Angle-dependent electron spin resonance (ESR) measurements are performed at a low temperature of 1.6 K and at an ESR frequency of 4.4 GHz utilizing a superconducting planar microwave resonator in a $^4$He-cryostat in combination with in-situ sample rotation. The obtained ESR g-factor of YbRh$_2$Si$_2$ as a function of the crystallographic angle is consistent with results of previous measurements using conventional ESR spectrometers at higher frequencies and fields. Perspectives to implement this experimental approach into a dilution refrigerator and to reach the magnetically ordered phase of YbRh$_2$Si$_2$ are discussed.

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Linda Bondorf, Manfred Beutel, Markus Thiemann, Martin Dressel, Daniel Bothner, Jörg Sichelschmidt, Kristin Kliemt, Cornelius Krellner, Marc Scheffler. 2017-11-15. Angle-dependent electron spin resonance of YbRh$_2$Si$_2$ measured with planar microwave resonators and in-situ rotation. https://doi.org/10.1016/j.physb.2017.10.046

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