Jang, Seohee Jeon, Seung-Woo Shiga, Takuma Shin, Jeeyoung Han, Sangwook Park, Woosung 2026-03-27T01:00:18Z 2026-03-27T01:00:18Z 2026-03-24 2026-03 https://pubs.kist.re.kr/handle/201004/154470 While the interplay between phonon and boundary dictates thermal transport at the nanoscale, the spectral manipulation of phonon-boundary scattering is insufficiently demonstrated yet. Here, we choose a single-crystal diamond nanobeam, a material with one of the highest Debye temperature materials, to investigate the impact of modulated phonon-boundary scattering with a temperature knob. The thermal conductivity of nanobeams is measured from room temperature down to similar to 140 K, and we find that the value monotonically decreases scaling with T-similar to 1.07. Compared to the model prediction based on the Boltzmann transport equation combined with ab initio calculation, we find that the experimental data increasingly deviate from the model prediction with diffuse phonon scattering as the temperature decreases. The deviation indicates the increasing portion of non-diffuse phonon-boundary scattering. Our analysis indicates that specular phonon-boundary scattering is more sensitive to temperature in single-crystal diamond compared to that of silicon. This work suggests that the diamond is a potential material platform to manipulate wave-like phonon conduction above 100 K. English Wiley-VCH Verlag Thermally Modulated Specular Phonon Transport in a High-Debye-Temperature Diamond Nanobeam Article 10.1002/advs.202523242 1 Advanced Science Advanced Science Y scie scopus 2-s2.0-105031931395 Chemistry, Multidisciplinary Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science Article; Early Access HEAT-CONDUCTION SILICON SCATTERING FILMS boundary scattering diamond nanobeams phonon transport