Spin-polarized transport through 2-D quantum materials

Abstract

newlineAbstract newlineDue to the growing demand for the miniaturization of electronic devices, there is an ur- newlinegent requirement to develop novel materials that can facilitate the design of energy-efficient newlinenano-scale electronic circuits. Two-dimensional (2D) quantum materials, owing to their newlineunique electronic properties, have emerged as promising candidates for future electronic de- newlinevices. Understanding the spin-polarized transport phenomena in these materials is crucial newlinefor the development of spintronics, offering potential advantages in spin-based information newlineprocessing and storage. This thesis investigates the spin-polarized transport characteristics newlineof various 2-D quantum materials through theoretical modeling and low-temperature-based newlinescanning probe techniques. newlineThe thesis is divided into two parts: The first part contains our work on a family of newlinevdW 2-D ferromagnets particularly those with the general formula Fe n GeTe 2 (where n=3,4) newlinewhich possess desirable characteristics such as large electrical conductivity, a high ferro- newlinemagnetic Curie temperature, and strong saturation magnetization for application in next- newlinegeneration spintronic devices. We have investigated the interplay of various quantum phe- newlinenomena in the aforementioned vdW ferromagnets using low-temperature-based scanning newlineprobe techniques. Furthermore, to enable efficient detection of Majorana modes in topolog- newlineical superconductors, crucial for fault-tolerant quantum computing, in the second part of the newlinethesis we have proposed a tunneling setup with weakly coupled Majorana nanowires. The newlinesetup offers controlled detection by manipulating the presence of a zero-bias conductance newlinepeak (ZBCP) based on wire parity. The major results, procured in this work are highlighted newlinebelow. newlineMeasurement of transport spin polarization of the vdW ferromagnets Fe 3 GeTe 2 newlineand Fe 4 GeTe 2 : We performed spin-resolved point contact Andreev reflection spectroscopy newlineof the mesoscopic junctions of these ferromagnets with conventional superconductors. The newlineresults revealed a ve