Open Collections

UBC Undergraduate Research

Contactless Measurements of Metal-Insulator Transitions using Toroidal Loop-Gap Resonators Kennedy, Ian R.

Abstract

We have used a toroidal loop-gap resonator (TLGR) to make sensitive contactless mea- surements of the so-called Verwey transition in Fe₃O₄ (magnetite) at microwave frequencies. In this metal-insulator transition, the sample’s resitivity increases by up to two orders of magnitude as it is cooled below 120 K. In our project a single-crystal sample of Fe₃O₄ is suspended in the bore of the TLGR. Microwave power absorption by the sample lowers the quality factor of the measured resonance. The observed changes in the quality factor are used to determine the temperature dependence of the sample’s resistivity. This project presents a characterization of the TLGR, design features of the low-temperature apparatus, the experimental results, as well as future considerations.

Item Metadata

Title
Contactless Measurements of Metal-Insulator Transitions using Toroidal Loop-Gap Resonators
Creator
Kennedy, Ian R.
Date Issued
2022-05
Description
We have used a toroidal loop-gap resonator (TLGR) to make sensitive contactless mea- surements of the so-called Verwey transition in Fe₃O₄ (magnetite) at microwave frequencies. In this metal-insulator transition, the sample’s resitivity increases by up to two orders of magnitude as it is cooled below 120 K. In our project a single-crystal sample of Fe₃O₄ is suspended in the bore of the TLGR. Microwave power absorption by the sample lowers the quality factor of the measured resonance. The observed changes in the quality factor are used to determine the temperature dependence of the sample’s resistivity. This project presents a characterization of the TLGR, design features of the low-temperature apparatus, the experimental results, as well as future considerations.
Genre
Graduating Project
Type
Text
Language
eng
Series
University of British Columbia. PHYS 449
Date Available
2022-05-20
Provider
Vancouver : University of British Columbia Library
Rights
Attribution-NoDerivatives 4.0 International
DOI
10.14288/1.0413654
URI
http://hdl.handle.net/2429/81603
Affiliation
Science, Irving K. Barber Faculty of (Okanagan); Computer Science, Mathematics, Physics and Statistics, Department of (Okanagan)
Peer Review Status
Unreviewed
Scholarly Level
Undergraduate
Rights URI
http://creativecommons.org/licenses/by-nd/4.0/
Aggregated Source Repository
DSpace

Item Media

Item Citations and Data

Rights

Attribution-NoDerivatives 4.0 International