Anomalous Proximitized Transport Properties in Heterostructures Built on Geometrically Frustrated Lattice

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.