CAREER: Spin and Spin Coherence Dynamics in One- Dimensional Semiconductor Nanostructures

University Of Maryland, College Park, College Park MD

Investigators

Abstract

Non-Technical Abstract: This Faculty Career project experimentally explores unique and novel spin dependent phenomena in one dimension (1D). This is a fascinating new research direction in the field of Spintronics that represents a new paradigm of electronics and utilizes electron spin rather than charge for device functionality. There are many exotic new spin- related fundamental physics in 1D condensed matter semiconductor systems due to their unusual structural and electronic properties, such as spin-charge separation. To achieve these, chemically synthesized Group II-VI and III-V 1D semiconductor nanostructures with tunable structural and physical properties will be applied as 1D model systems. The state-of-the-art ultrafast optical spin resonance techniques will be employed to investigate the spatial and temporal evolutions of spin dynamics in as-synthesized 1D nanostructures. From the practical point of view, 1D condensed matter systems represent the smallest dimension structures that can be used for efficient information transport based on the spin degree of freedom. Ultimately, results from this project will be critical to the function and integration of NanoSpintronic technology and lead to the advance in quantum information processing and quantum computation. An important component of this project, in addition to direct training provided to graduated students, is the integration of research with undergraduate education program. This will involve developing a new undergraduate course, aiming at exposing motivated undergraduate students to independent research in nanoscience early in their college careers and serving as a platform to transform their knowledge learnt from traditional course to research experience. This course will also fill the need for research opportunities for undergraduates in the recently initiated Interdisciplinary Minor Program in Nanoscale Science and Technology in the University of Maryland. Technical Abstract: The object of this Faculty Career project is to develop fundamental experimentally based understanding of spin and spin coherence dynamics in one-dimensional (1D) condensed matter semiconductor systems with all-optical far-field and near-field spin resonance techniques. Many exotic new spin- related physics have been predicted for real 1D semiconductor systems due to their unique spin-spin and spin-charge interactions as well as spin couplings with their dissipate environment. In this project chemically synthesized Group II-VI and III-V 1D semiconductor nanostructures with controllable structural and physical properties will be applied as 1D model systems and combined with all optical spin resonance techniques to probe spin dynamics within nanostructures. Several fundamental issues will be focused on, including spin coherence lifetimes, electron and exciton Lande g-factors, intrinsic spin relaxation mechanisms, dimensionality and anisotropic effects, 1D spin diffusion and spin coherence transport, coherent light-matter-spin interactions within 1D nanostructures and spin condensate process in 1D nanocavity. 1D condensed matter systems also represent the smallest dimension structures that can be used for efficient information transport based on the spin degree of freedom. Ultimately, these studies will be critical to the function and integration of NanoSpintronic technology. An important component of this project, in addition to direct training provided to graduated students, is the integration of research with undergraduate education program. This will involve developing a new undergraduate course, aiming at exposing motivated undergraduate students to independent research in nanophysics and nanomaterial sciences early in their college careers and serving as a platform to transform their knowledge learnt from traditional course to research experience.