Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 19: Poster Session: Correlated Electrons 1
TT 19.8: Poster
Montag, 20. März 2017, 15:00–19:00, P2-EG
Electron spin resonance as a function of frequency, field, temperature, and angle using broadband and resonant planar microwave devices applied to YbRh2Si2 and ruby — •Linda Bondorf1, Manfred Beutel1, Wolfgang Voesch1, Markus Thiemann1, Kristin Kliemt2, Cornelius Krellner2, Martin Dressel1, and Marc Scheffler1 — 11. Physikalisches Institut, Universität Stuttgart, Germany — 2Goethe-Universität, Frankfurt am Main, Germany
The quantum-critical heavy-fermion material YbRh2Si2 shows strong magnetic anisotropy and exhibits antiferromagnetic order at temperatures below 70 mK and magnetic fields below 60 mT. Electron spin resonance (ESR) measurements on YbRh2Si2 at such low temperatures and fields are highly desired but out of reach for conventional ESR spectrometers. These limitations can be overcome with resonant and broadband planar microwave devices as ESR probes [1, 2].
Here we present an ESR setup that enables frequency-, magnetic field-, temperature-, and angle-dependent measurements using coplanar structures. We demonstrate this technique through broadband ESR measurements (up to 20 GHz) on ruby with in-situ sample rotation inside a 4He cryostat. Angle-dependent measurements with enhanced sensitivity on YbRh2Si2 are performed down to 4.4 GHz and 1.6 K using a superconducting coplanar resonator, and extensions of this approach to mK temperatures will be discussed.
[1] M. Scheffler et al., Phys. Status Solidi B 250, 439 (2013).
[2] Y. Wiemann et al., Appl. Phys. Lett. 106, 193505 (2015).