Influence of pressure on properties of multi-gap type-I superconductor BeAu

Abstract

We report on studies of the superconducting and normal state properties of the noncentrosymmetric superconductor BeAu under hydrostatic pressure conditions. The room-temperature equation of state (EOS) reveals the values of the bulk modulus ($B_0$) and its first derivative ($B_0^{\prime }$) at ambient pressure to be $B_0\simeq 132$~GPa and $B_0^{\prime }\simeq 30$, respectively. Up to the highest pressures studied ($p\simeq 2.2$~GPa), BeAu remains a multi-gap type-I superconductor. The analysis of $B_{\mathrm{c}}(T,p)$ data within the self-consistent two-gap approach suggests the presence of two superconducting energy gaps, with the gap-to-$T_{\mathrm{c}}$ ratios ${\Delta }_1/k_{\mathrm{B}}{T}_{\mathrm{c}}\sim 2.3$ and ${\Delta }_2/k_{\mathrm{B}}{T}_{\mathrm{c}}\sim 1.1$ for the larger and smaller gaps, respectively [$\Delta =\Delta (0)$ is the zero-temperature value of the gap and $k_{\mathrm{B}}$ is the Boltzmann constant]. With increasing pressure, ${\Delta }_1/k_{\mathrm{B}}{T}_{\mathrm{c}}$ increases while ${\Delta }_2/k_{\mathrm{B}}{T}_{\mathrm{c}}$ decreases, suggesting that pressure enhances (weakens) the coupling strength between the superconducting carriers within the bands where the larger (smaller) superconducting energy gap has opened. The superconducting transition temperature $T_{\mathrm{c}}$, \textcolor{black}{the zero-temperature values of the superconducting gaps ${\Delta }_1$ and ${\Delta }_2$} and the zero-temperature value of the thermodynamic critical field $B_{\mathrm{c}}(0)$ decrease with increasing pressure, with the rates of $\mathrm{d}{T}_{\mathrm{c}}/\mathrm{d}p\simeq -0.195$~K/GPa, \textcolor{black}{$\mathrm{d}{\Delta }_1/\mathrm{d}p\simeq -0.034$~meV/GPa, $\mathrm{d}{\Delta }_2/\mathrm{d}p\simeq -0.029$~meV/GPa,} and $\mathrm{d}{B}_{\mathrm{c}}(0)/\mathrm{d}p=-2.65(1)$~mT/GPa, respectively. The measured $B_{\mathrm{c}}(0)$ values plotted as a function of $T_{\mathrm{c}}$ follow an empirical scaling relation established for conventional type-I superconductors.

References in corpus (27)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Eliashberg Theory: a short review
• Superfluid density and specific heat within self-consistent scheme for two-band superconductor
• Specific heat and $\mu$SR study on the noncentrosymmetric superconductor LaRhSi3
• Type I superconductivity in the Dirac semimetal PdTe2
• Type-I superconductivity in PdTe${}_2$ probed by $\mu$SR
• Exceptional type-I superconductivity of the layered silver oxide Ag${}_5$Pb${}_2$O${}_6$
• Type-I superconductivity in noncentrosymmetric NbGe${}_2$
• muSR and Magnetometry Study of the Type-I Superconductor BeAu
• Type-I superconductivity in noncentrosymmetric superconductor AuBe
• Coexistence of type-I and type-II superconductivity signatures in ZrB12 probed by muon spin rotation measurements
• Perspective on the muon-spin rotation/relaxation under hydrostatic pressure
• Anisotropic type-I superconductivity and anomalous superfluid density in OsB 2
• Multiple-gap response of type-I noncentrosymmetric BeAu superconductor
• The single- vs. two-gap scenario: the specific heat and the thermodynamic critical field of BeAu superconductor
• Type-I superconductivity in Al${}_6$Re
• Multi-Band Superconductivity and the Steep Band -- Flat Band Scenario
• Muon spin rotation study of type-I superconductivity: elemental $\beta -$Sn
• On the superconducting nature of the Bi-II phase of elemental Bismuth
• An investigation of type-I superconductivity in single crystal of Pb2Pd
• Self-consistent two-gap approach in studying multi-band superconductivity in NdFeAsO${}_{0.65}$F${}_{0.35}$
• Anomalous gap ratio in anisotropic superconductors: aluminum under pressure
• Isotropic single gap superconductivity of elemental Pb: the `smiling' approach
• Chiral Meissner effect in time-reversal invariant Weyl superconductors
• Spectroscopic evidence of multi-gap superconductivity in non-centrosymmetric AuBe
• Optical setup for a piston-cylinder type pressure cell: a double-volume approach

Cited by in corpus (2)

• Thermodynamic evidence for a pressure-driven crossover from strong- to weak-coupling superconductivity in Pb
• Fermi surface and topology of multiband superconductor BeAu