Superconductivity in a low carrier density system: A single crystal study of cubic Y3Ru4Ge13

• Published in: Physica. C, Superconductivity Vol. 492; pp. 90 - 95
• Main Authors: Prakash, Om, Thamizhavel, A., Nigam, A.K., Ramakrishnan, S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-09-2013; Elsevier
• Subjects: Carrier density; Carriers; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Crystal structure; Electrical resistivity; Exact sciences and technology; Hall effect; Heat capacity; Magnetic permeability; Metals, alloys and compounds (a15, 001c15, laves phases, chevrel phases, borocarbides, etc.); Mixed state, critical fields, and surface sheath; Physics; Properties of type I and type II superconductors; Semimetal; Single crystals; Superconducting materials (excluding high-tc compounds); Superconductivity; Hall effect; Semimetal; Superconductivity; Cubic lattices; Electrical conductivity; Ruthenium Yttrium Germanides Mixed; Critical field; Magnetic susceptibility; Specific heat; Monocrystals; Superconductors; Semimetals; Carrier density; Crystal structure
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/j.physc.2013.05.014

•Y3Ru4Ge13 is a low carrier density (1020/cm3) semimetal and exhibits bulk superconductivity.•The superconductivity arises due to inter-valley electron-phonon interactions.•Hall coefficient has unusual temperature dependence similar to both High-Tc and layered compounds like MgB2.•These classes of materials have good thermoelectric properties.•We need good data on single crystals for further understanding of thermoelectric properties.
We have successfully grown the single crystal of a low carrier density system Y3Ru4Ge13 which crystallises in the cubic crystal structure with the space group Pm3n. Y3Ru4Ge13 exhibits superconductivity below 2.85K as determined from the electrical resistivity, magnetic susceptibility and heat capacity measurements. The bulk measurements indicate multi-band superconductivity in this low carrier system. Hall effect measurements show that the Hall coefficient RH is positive and it decreases rapidly with temperature which is highly unusual. The simple estimation of the carrier concentration gives a value (1020/cm3) which is 2–3 orders of magnitude lower than that of a conventional metal like Cu which seems to suggest that Y3Ru4Ge13 is a semimetal that display multiband superconductivity.