Doctoral Dissertations
Date of Award
12-2024
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Major
Physics
Major Professor
Haidong Zhou
Committee Members
Jian Liu, Cristian Batista, Dustin Gilbert
Abstract
While geometrically frustrated quantum magnets (GFQMs) host rich exotic spin states with potentials for revolutionary quantum technologies, most of them are necessarily good insulators which are difficult to be integrated with modern electrical circuit. The grand challenge is to electrically detect the emergent fluctuations and excitations by introducing charge carriers that interact with the localized spins without destroying their collective spin states. This thesis consists of three projects that design a new series of heterostructures which combine the insulating GFQMs and spin-orbit entangled correlated metal to study the exotic magnetic excitations in GFQMs. Chapter 1 describes the background to the magnetic properties of geometrically frustrated pyrochlore magnets, and gives the motivation of the original research presented later. Chapter 2 describes experimental techniques including heterostructure synthesis and heterostructure characteristics. In chapter 3, Bi2Ir2O7//Dy2Ti2O7 heterostructure is designed to capture the characteristic angular and temperature dependence of ice-rule-breaking transition. In chapter 4, we design a Bi2Ir2O7/Yb2Ti2O7 heterostructure to show that the proximitized transport in Bi2Ir2O7 can be effectively tuned by magnetic field through suppressing the quantum spin fluctuations as well as inducing transitions via magnetic anisotropy in Yb2Ti2O7. In chapter 5, by synthesizing 18nm-thick Dy2Ti2O7 thin film on YSZ substrate and capped by a thin conductive Bi2Ir2O7 layer, it confirmed that the ice-rule-breaking phase transition survives in the thin film but with a significantly reduced effective nearest-neighbor interaction compared to the bulk crystal.
Recommended Citation
Xing, Chengkun, "Anomalous Proximitized Transport Properties in Heterostructures Built on Geometrically Frustrated Lattice. " PhD diss., University of Tennessee, 2024.
https://trace.tennessee.edu/utk_graddiss/11401
