CAREER: Quantum Optical Measurements of Exciton Fluids in Confined Systems

Michigan State University, East Lansing MI

Investigators

Abstract

****NON-TECHNICAL ABSTRACT**** Light is now an essential tool that can be used to manipulate matter and also to create new states of matter. This Faculty Early Career Award supports a program that will merge quantum measurements and ultrafast spectroscopies to investigate light-matter hybrid excitations such as excitons in semiconductor nanostructures. Excitons, the solid-state analog of a positronium atom, play a central role in the optical properties and electronic structure of solids. They exhibit strong radiation-matter coupling and are thus ideal for exploration of light-matter collective phenomena in quantum-confined structures. This project is expected to contribute to the fundamental understanding and control of light-matter interactions in nanostructures, which are important for developing new quantum materials and optoelectronic devices for computation and communication. Graduate and undergraduate students in this program will learn advanced ultrafast spectroscopies and low temperature techniques used to investigate nanostructures and quantum materials. The education component includes the development of a summer workshop to introduce graduate students to the research environment and to learn optical methods for studying condensed matter systems. Experiments in quantum optics and laser spectroscopy will be incorporated into the undergraduate curriculum. Outreach activities include public lectures, demonstrations, and hands-on experiments about optics in daily life for high school teachers, K-12 students, and underrepresented pre-college students. ****TECHNICAL ABSTRACT**** This Faculty Early Career Award supports a project that will merge quantum optical measurements with ultrafast spectroscopic techniques to investigate collective phenomena in cold exciton fluids in quantum confined semiconductor structures. In order to clarify the nature of these apparently ordered, but actually non-equilibrium exciton fluids, the project will attempt to determine: (a) how the statistical properties of light fields are transformed through the formation of excitons or electron-hole carriers, and (b) how the characteristics of self-luminescent photons reflect the interactions, correlations, and collective excitations. Spatio-temporal correlations and fluctuations of excitonic fluids in confined low-dimensional semiconductor systems will be probed. After creating dense cold excitons, the self-luminescence or spontaneous order will be characterized with precise control of the amplitude, phase, polarization, coherence, and fluctuations of the light fields. The education component includes the development of a summer workshop to introduce graduate students to the research environment and to learn optical methods for studying condensed matter systems. Experiments in quantum optics and laser spectroscopy will be incorporated into the undergraduate curriculum. Outreach activities include public lectures, demonstrations, and hands-on experiments about optics in daily life for high school teachers, K-12 students, and underrepresented pre-college students.