2024/09/28 by Il‐Ho Kim, Noah Kurinsky, Kim, I. +7 · 1 citation
Engineering · Physics and Astronomy · #Advanced Semiconductor Detectors and Materials #Atomic and Subatomic Physics Research #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Instrumentation and Detectors (physics.ins-det) #Nuclear Experiment (nucl-ex) #Quantum optics and atomic interactions
paper · pdf · doi:10.48550/arxiv.2409.19238
openalex publication_date 2024/09/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We explored the efficacy of lab-grown diamonds as potential target materials for the direct detection of sub-GeV dark matter~(DM) using metallic magnetic calorimeters~(MMCs). Diamond, with its excellent phononic properties and the low atomic mass of the constituent carbon, can play a crucial role in detecting low-mass dark matter particles. The relatively long electron-hole pair lifetime inside the crystal may provide discrimination power between the DM-induced nuclear recoil events and the background-induced electron recoil events. Utilizing the the fast response times of the MMCs and their unique geometric versatility, we deployed a novel methodology for quantifying phonon dynamics inside diamond crystals. We demonstrated that lab-grown diamond crystals fabricated via the chemical vapor deposition~(CVD) technique can satisfy the stringent quality requirements for sub-GeV dark matter searches. The high-quality polycrystalline CVD diamond showed a superior athermal phonon collection efficiency compared to that of the reference sapphire crystal, and achieved energy resolution 62.7~eV at the 8.05~keV copper fluorescence line. With this energy resolution, we explored the low-energy range below 100~eV and confirmed the existence of so-called low-energy excess~(LEE) reported by multiple cryogenic experiments.