Guardado en:
| Autores principales: | , , , , , , |
|---|---|
| Formato: | Preprint |
| Publicado: |
2024
|
| Materias: | |
| Acceso en línea: | https://arxiv.org/abs/2403.11341 |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| _version_ | 1866912549956485120 |
|---|---|
| author | Ahrling, R. Mitdank, R. Popp, A. Rehm, J. Akhtar, A. Galazka, Z. Fischer, S. F. |
| author_facet | Ahrling, R. Mitdank, R. Popp, A. Rehm, J. Akhtar, A. Galazka, Z. Fischer, S. F. |
| contents | The anisotropic thermal conductivity and the phonon mean free path (mfp) in monoclinic $β$-Ga$_2$O$_3$ single crystals and homoepitaxial films of several $μ$m were determined using the 3$ω$-method in the temperature range from 10K-300 K. The measured effective thermal conductivity of both, single crystal and homoepitaxial films are in the order of 20 W/(mK) at room temperature, below 30 K it increases with a maximum of 1000 to 2000 W/(mK) and decreases with T$^3$ below 25 K. Analysis of the phonon mfp shows a dominance of phonon-phonon-Umklapp scattering above 80 K, below which the influence of point-defect scattering is observed. Below 30 K the phonon mfp increases until it is limited by the total $β$-Ga$_2$O$_3$ sample size. A crossover from resistive to ballistic phonon transport is observed below 20 K and boundary effects of the total sample size become dominant. This reveals that the homoepitaxial film-substrate interface is highly phonon-transparent. The resistive and ballistic phonon transport regimes in $β$-Ga$_2$O$_3$ are discussed corresponding to the models of Callaway and Majumdar, respectively. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2403_11341 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Resistive and ballistic phonon transport in $β$-Ga$_2$O$_3$ Ahrling, R. Mitdank, R. Popp, A. Rehm, J. Akhtar, A. Galazka, Z. Fischer, S. F. Materials Science The anisotropic thermal conductivity and the phonon mean free path (mfp) in monoclinic $β$-Ga$_2$O$_3$ single crystals and homoepitaxial films of several $μ$m were determined using the 3$ω$-method in the temperature range from 10K-300 K. The measured effective thermal conductivity of both, single crystal and homoepitaxial films are in the order of 20 W/(mK) at room temperature, below 30 K it increases with a maximum of 1000 to 2000 W/(mK) and decreases with T$^3$ below 25 K. Analysis of the phonon mfp shows a dominance of phonon-phonon-Umklapp scattering above 80 K, below which the influence of point-defect scattering is observed. Below 30 K the phonon mfp increases until it is limited by the total $β$-Ga$_2$O$_3$ sample size. A crossover from resistive to ballistic phonon transport is observed below 20 K and boundary effects of the total sample size become dominant. This reveals that the homoepitaxial film-substrate interface is highly phonon-transparent. The resistive and ballistic phonon transport regimes in $β$-Ga$_2$O$_3$ are discussed corresponding to the models of Callaway and Majumdar, respectively. |
| title | Resistive and ballistic phonon transport in $β$-Ga$_2$O$_3$ |
| topic | Materials Science |
| url | https://arxiv.org/abs/2403.11341 |