Room-Temperature Two-Dimensional Polaritronics with van der Waals Heterostructures
Abstract
The overarching goal of the project is to establish a versatile room temperature two-dimensional van der Waals crystal (vdWC) polariton system, as a bridge from the discovery of new manybody phenomena to novel photonic technologies Ð the polaritronics. Cavity exciton-polariton systems integrate strong optical nonlinearities and spontaneous coherence into a semiconductor photonic platform. Ripe with potential for new many-body physics phenomena, such as spontaneous spin polarization and non-equilibrium superfluidity, they also promise new photonic technologies. Lasing without population inversion, THz optical switching and polariton interferometers have all been demonstrated in GaAs systems, albeit at <20 K. Accessing a broader range of quantum phenomena at higher temperatures requires much stronger exciton-photon coupling and greater control over system properties. Recently, optically active van der Waals crystals such as transition-metal dichalcogenides promise extraordinary exciton-photon coupling strengths, allows unprecedented flexibility for integration of different vdWCs and other solids, and features many unique properties for novel phenomena, such as the coupled spin and valley degrees of freedom, strong phonon-charge interactions, and stable multi-charge cluster excitations. The project aims to exploit these properties and develop room-temperature polaritronis based on van der Waals materials. We will approach this goal via a concerted, multi-disciplinary effort, concentrating on major advances in materials and structures, polariton physics, and new phenomena and devices enabled by 2D vdWCs. Our objectives in this program are to: 1. Demonstrate room temperature 2D vdWC-polaritons. We will achieve this by creating a library of building blocks for 2D polaritronics. We will develop methods to create high-quality 2D vdWCs, to overlay electrical contacts, and to integrate the HS in photonic structures. This will lay the technological foundation for 2D polaritronics. 2. Control the properties of 2D vdWC-polaritons. We will achieve a quantitative understanding of the properties of electrons, holes, photons and their interactions in the materials and structures we develop. We will control the competition between dark and bright states, engineer the inter-related spin-valley degrees of freedom, couple optical and electronic lattices potentials, and control nonlinearity and dynamics of the polaritons. The aim is to unravel new phenomena unique to 2D vdWC-polaritons and to develop innovative device concepts. 3. Demonstrate room temperature polariton condensate and superfluidity for new types of emitters, detectors, and routers. As a culmination of the previous two efforts, we will demonstrate ultra-low threshold and high-efficiency room temperature polariton lasers based on polariton condensation and a new Andreev pumping mechanism; an efficient artificial photosynthetic device based on long-range transport of polaritons, and a fast and efficient optical routers utilizing the unusually strong nonlinearity and charge-photon coupling of 2D vdWCs. The program will be supported by technical efforts on fabrication of vdWC-cavities with integrated electrical control, and theoretical, numerical and experimental research on the properties of vsWC polaritons, polariton condensates and polariton devices.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 06, 2018
- Source ID
- W911NF1710312
Entities
People
- Hui Deng
Organizations
- Army Contracting Command
- United States Army
- University of Michigan