Engineering thermal emission using bound states in the continuum
Abstract
Engineering thermal emission using bound states in the continuum(Approved for Public Release)The overall goal of this project is toharness the topological nature of Bound States in the Continuum supported in plasmonic metasurfaces to engineer thermal emission properties. To accomplish this objective, the impact of the geometry of the quasi-BIC metasurface elements in achieving near-unity emissivity and spectral coherence must be investigated, and the role of symmetry-protected modes in the quasi-BIC system in imparting unidirectional emission must be understood. Thermal emitters typically produce radiation with a broad spectrum, as dictated by Planck s law of radiation. The incoherent nature of thermal emission makes it challenge to control and tune thermal emission properties. Consequently, there is a demand for achieving narrow-bandwidth, unidirectional thermal emission with high emissivity and polarizationcontrol within specific wavelength ranges. Meeting this need has remained elusive. We propose plasmonic thermal metasurfaces powered by the physics of symmetry-protected bound states in the continuum (BIC) to achieve stable unidirectional thermal emission, whose spectral properties is robust against temperature changes. We will introduce slotted plasmonic quasi-BIC metasurfaces that offer three degrees of freedom for controlling thermal emission, a novel approach that has not been explored before in thermal emission engineering.Specific objectives of this project include: (1) understand the influence of the geometry of quasi-BIC metasurface in achieving near-unity emissivity and spectral coherence; (2) understand the impact of the properties of symmetry protected quasi-BIC in achieving directional thermal emission with polarization control; and (3) experimentally demonstrate unidirectional thermal emission with record Q factor (>100), and near unity emissivity using plasmonic quasi-BIC thermal metasurface. Intellectual Merit:Specific contributions to technology and science enabled by this research include: (a) understanding of how to harness the topological nature of bound states in the continuum to design and realize enhanced electromagnetic fields and near unity emissivity in thermal metasurfaces; (b) discovery of a new approach to simultaneously tune quality factor and control optical absorption by harnessing slotted cavities in quasi-BIC plasmonic metasurfaces; (c) the first experiment to harness quasi-bound states in the continuum with slotted cavitiesfor unidirectional thermal emission engineering.Impact on DoD capabilities:The demonstration of unidirectional thermal emission enabled by quasi-BIC metasurfaces will significantly impact the Navy and DoD in several ways. This could be harnessed for infrared beacons for search and rescue operations, free-space communication, infrared signature management for precise control of heat signaturesemitted by naval vessels, infrared countermeasures to confuse enemy targeting systems, thermal management by optimizing heat dissipation and improve overall energy efficiency of on-board components on naval vessels. Furthermore, findings from the proposed research could also be adapted to realize spectrally-selective light sources for gas detection and miniaturized sensors for health monitoring.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Dec 15, 2023
- Source ID
- N000142412085
Entities
People
- Justus Ndukaife
Organizations
- Office of Naval Research
- United States Navy
- Vanderbilt University