  Stoichiometric near room-temperature superconductors (i.e., $H_3S$ and
$LaH_{10}$) exhibit so high ground state upper critical field, $B_{c2}(0)>100
T$, that the magnetic phase diagram in these materials cannot be measured in
non-destructive experiments. However, recently, Semenok et al (arXiv2203.06500)
proposed the idea to explore full magnetic phase diagram in NRTS samples in
which the superconducting order parameter is suppressed by the magnetic element
doping. If the element is uniformly distributed in the material, then the
theory of the electron-phonon mediated superconductivity predicts the
suppression of the order parameter in three-dimensional s-wave superconductor.
Semenok et al (arXiv2203.06500) experimentally proved this idea by substituting
La with the magnetic rare earth Nd in the $La_{1-x}Nd_{x}H_{10-y}$. As a
result, $T_c$ in the $La_{1-x}Nd_{x}H_{10-y}$ (x=0.09) decreases to Tc~120 K,
and the upper critical field decreases to $B_{c2}(T=41 K)=55 T$. While the
exact hydrogen content should be further established in the
$La_{1-x}Nd_{x}H_{10-y}$ (because similar $T_c$ suppression was observed in
hydrogen deficient $LaH_{10-y}$ reported by Drozdov et al (2019 Nature 569
528)), a significant part of the full magnetic phase diagram for
$La_{1-x}Nd_{x}H_{10-y}$ (x=0.09) was measured. Here we analyzed reported
Semenok et al (arXiv2203.06500) data for $La_{1-x}Nd_{x}H_{10-y}$ (x=0.09)
compressed at P=180 GPa and deduced: (a) Debye temperature, $T_{\theta}=1156
K$; (b) the electron-phonon coupling constant, ${\lambda}_{e-ph}=1.65$; (c) the
ground state superconducting energy gap, ${\Delta}(0)=20.2 meV$; (d) the
gap-to-transition temperature ratio, $2{\Delta}(0)/k_BT_c=4.0$; and (e) the
relative jump in specific heat at $T_c$, ${\Delta}C/C=1.68$. The deduced values
indicate that $La_{1-x}Nd_{x}H_{10-y}$ (x=0.09; P=180 GPa) is moderately strong
coupled s-wave superconductor.
