Debye temperature, electron-phonon coupling constant, and moderate nonadiabaticity in highly-compressed I-43d-TaH3 superconductor

Recently, He et al (arXiv2212.13739 (2022)) reported on the discovery of high-temperature superconductivity in highly-compressed polyhydride of tantalum. At pressure ${\it P}=197 GPa$, the polyhydride I-43d-phase of $TaH_3$ exhibits zero-resistance transition temperature $T_{c,zero}=25.6 K$. Measurements of the low-temperature magnetoresistance showed that this superconductor has the ground state upper critical field (defined by the zero resistance criterion) $B_{c2}(0) = 11 Tesla$. Here, we performed detailed analysis of the reported experimental data by He et al (arXiv2212.13739 (2022)) and deduced several parameters of the I-43d-phase of $TaH_3$: (a) the Debye temperature, $T_{\theta}=263 K$, (b) the electron-phonon coupling constant, ${\lambda}_{e-ph}=1.53$; (c) the Fermi temperature $T_{F}=1324 K$; (d) the strength of nonadiabaticity, $T_{\theta}/T_F =0.19$; (e) and the ratio of $T_{c}/T_{F} =0.0185 $ which implies that I-43d-phase of $TaH_3$ falls in unconventional superconductors band in the Uemura plot. Deduced parameters indicate that the I-43d-phase of $TaH_3$ (${\it P}=197 GPa$) can be classified as typical unconventional high-temperature superconductor.