Design and build low-temperature probe-head for FMR spectroscopy of 2D materials

Low-temperature ferromagnetic resonance (FMR) spectroscopy measurement will be beneficial to understanding the spin dynamics of emerging 2D materials. The probe-head for low-temperature FMR is difficult because modulation coils, a microwave stripline with connection, and other electrical connections must fit within the sealed cryostat, typically a 30mm diameter sealed tube. We describe the design and manufacturing processes used to create an ergonomic sample probe head capable of operating in a closed-cycle. The probe head was constructed from garolite (G10/FR4) because it has a low thermal expansion coefficient and it is nonmagnetic. The microwave stripline holder was constructed to hold modulation coils, enabling a lock-in detection scheme to detect the weak signal. A heating wire and a type E thermocouple were placed around the microwave stripline holder for temperature control and measurement. A perforated G10 tube was used to allow for evenly distributed gas flow and for temperature stability. We demonstrated room-temperature FMR on 100nm CoFeB film using the newly designed sample holder as a proof of concept.

Description

Poster and abstract presented at the FYRE in STEM Showcase, 2024.
Research project completed at the Department of Mathematics, Statistics, and Physics.

Publisher

Wichita State University

Series

FYRE in STEM 2024

URI

https://hdl.handle.net/10057/27782

Collections

FYRE in STEM 2024