Dark matter remains one of the most profound mysteries in modern physics, with axions, a hypothetical particle proposed to resolve the strong CP problem, standing as a compelling candidate. Among various experimental strategies, cavity haloscopes currently offer the most sensitive method to detect axions, though their searches have largely been confined to axion masses below 10 μeV. However, recent theoretical developments suggest that the axion mass lies beyond this range. Higher-order cavity modes have been explored as a methodological approach to expand the search range, albeit with limited success in achieving both high sensitivity and broad tunability. In this work, we present a sensitive search for axions with masses around 21 μeV, utilizing the TM020 mode of a cylindrical cavity, which incorporated an innovative tuning mechanism. Our results reached 1.7 times the KSVZ sensitivity over 100 MHz, representing a significant improvement in this mass range and contributing to the experimental search for axion dark matter at higher masses.
@article{arxiv.2505.05095,
title = {Axion Dark Matter Search with Near-KSVZ Sensitivity Using the TM$_{020}$ Mode},
author = {Sungjae Bae and Junu Jeong and Younggeun Kim and SungWoo Youn and Jinsu Kim and Arjan F. van Loo and Yasunobu Nakamura and Seonjeong Oh and Taehyeon Seong and Sergey Uchaikin and Jihn E. Kim and Yannis K. Semertzidis},
journal= {arXiv preprint arXiv:2505.05095},
year = {2025}
}