EAGER: In-situ spectral phonon recycling in LED for improved thermal, power and performance efficiency

EAGER：LED 中的原位光谱声子回收可提高热、功率和性能效率

• 批准号: 2407260
• 负责人: Massoud Kaviany
• 金额: $ 12.52万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-15 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2407260&HistoricalAwards=false
• 关键词: EAGER; situ; spectral; phonon; recycling

Lighting consumes equivalent to 5% of total US electricity use according to US Energy Information Administration. The use of light emitting diodes (LEDs) has improved the lighting efficiency, but still more than 50% of the electrical energy is dissipated as heat (emitted phonons). Improving energy conversion and demonstrating timely and significant impact of phonon engineering using gallium-nitride GaN LED is the goal of this proposed EAGER. This will be done by adding a heterobarrier (HB) layer to the LED structure for a net absorption and recycling of phonon emissions that will provide improved power efficiency. The objectives are to theoretically predict the improvements and to fabricate and test the optimal design, aiming to demonstrate the proof-of-concept and make it available for technological implementations. Through collaboration with an GaN LED and display expert, the proposed improvement verifications can be implemented at commercial level resulting in significant national energy savings and enhanced device thermal management. Fundamental understanding and insightful use of the phonon-electron-photon interactions advance the heat transfer physics and engineering. The proposed research would be the first attempt at in-situ spectral-phonon recycling in LED using a graded HB. The research combines simulations of the phonon transport and recycling behavior to understand and advance the novel idea of phonon recycling, and also includes an experimental verification of the new concept. The one-year EAGER effort is therefore focused on demonstrating the new concept of phonon-recycling for LEDs, and if successful can provide significant paybacks in terms of energy savings. The proposed research advances the premise that the benefits of phonon-recycling via the HB is achieved through three distinct pathways: (a) reduced heat load resulting in a temperature decrease for LEDs (b) increased power efficiency, where the electric current in the LED harvests phonon energy, creating a net potential gain, and (c) enhanced photon emission spectra due to the net potential gain in the HB layer. The predictions in the proposed research use mesoscale (Boltzmann transport) interactions, which involves phonons, electrons and holes, and photons. The fabrication and testing/characterization of the optimal HB GaN LED will provide the first ever experimental demonstration of improvements in LED performance and energy savings via the use of a HB. The proposed research aligns with the Department of Energy solid-state lighting R&D goals for 2035 which would enable national energy savings equivalent to 3% of US energy consumption in 2022.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

根据美国能源情报署的数据，照明消耗相当于美国总用电量的5%。发光二极管（led）的使用提高了照明效率，但仍有50%以上的电能以热量（发出的声子）的形式散失。利用氮化镓GaN LED改善能量转换并及时展示声子工程的重大影响是本研究的目标。这将通过在LED结构中添加异位垒（HB）层来实现，以实现声子发射的净吸收和再循环，从而提高功率效率。目标是从理论上预测改进，并制造和测试最佳设计，旨在演示概念验证并使其可用于技术实现。通过与GaN LED和显示器专家的合作，提出的改进验证可以在商业层面上实施，从而显著节省国家能源并增强器件热管理。对声子-电子-光子相互作用的基本理解和深刻运用促进了传热物理和工程的发展。提出的研究将是第一次尝试使用分级HB在LED中进行原位光谱声子回收。该研究结合了声子输运和回收行为的模拟，以理解和推进声子回收的新思想，并包括对新概念的实验验证。因此，为期一年的EAGER工作重点是展示led声子回收的新概念，如果成功，可以在节能方面提供重大回报。该研究提出了一个前提，即通过HB进行声子回收的好处是通过三个不同的途径实现的：(a)减少热负荷，导致LED温度下降；(b)提高功率效率，LED中的电流收集声子能量，产生净潜在增益；(c)由于HB层的净潜在增益，光子发射光谱增强。拟议研究中的预测使用了中尺度（玻尔兹曼输运）相互作用，其中涉及声子、电子和空穴以及光子。最佳HB GaN LED的制造和测试/表征将首次提供通过使用HB来改善LED性能和节能的实验演示。拟议的研究与美国能源部2035年固态照明研发目标一致，该目标将使全国能源节约相当于2022年美国能源消耗的3%。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。