Purcell enhanced optical refrigeration

作     者：Ju, Peng Püschel, Stefan Shen, Kunhong Jin, Yuanbin Tanaka, Hiroki Li, Tongcang 

作者机构：Department of Physics and Astronomy Purdue University West LafayetteIN47907 United States  Max-Born-Str. 2 Berlin12489 Germany Elmore Family School of Electrical and Computer Engineering Purdue University West LafayetteIN47907 United States Birck Nanotechnology Center Purdue University West LafayetteIN47907 United States Purdue Quantum Science and Engineering Institute Purdue University West LafayetteIN47907 United States 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2024年

核心收录：

主　　题：Ground state 

摘      要：Optical refrigeration of solids with anti-Stokes fluorescence has been widely explored as a vibration-free cryogenic cooling technology. A minimum temperature of 87 K has been demonstrated with rare-earth ion doped crystals using optical refrigeration. However, the depletion of the upper-lying energy levels in the ground state manifold hinders further cooling to below liquid nitrogen (LN2) temperatures, confining its applications. In this work, we introduce a Purcell enhanced optical refrigeration method to circumvent this limitation. This approach enhances the emission of high energy photons by coupling to a nearby nanocavity, blue shifting the mean emission wavelength. Such Purcell enhanced emission facilitates cooling starting from a lower energy level in the ground state manifold, which exhibits a higher occupation below LN2 temperatures. Using our experimentally measured optical coefficients, our theoretical analysis predicts a minimum achievable temperature of 38 K for a Yb3+:YLiF4 nanocrystal near a cavity under realistic conditions. The proposed method is applicable to other rare-earth ion doped materials and semiconductors, and will have applications in creating superconducting and other quantum devices with solid-state cooling. Copyright © 2024, The Authors. All rights reserved.