Anisotropic Hc 2, thermodynamic and transport measurements, and pressure dependence of Tc in K2Cr3As3 single crystals
Abstract
We present a detailed study of single crystalline K2Cr3As3 and analyze its thermodynamic and transport properties, anisotropic Hc 2(T ) , and initial pressure dependence of Tc. In zero field, the temperature-dependent resistivity is metallic. Deviation from a linear temperature dependence is evident below 100 K and a T3 dependence is roughly followed from just above Tc (∼10 K ) to ∼40 K . Anisotropic Hc 2(T ) data were measured up to 140 kOe with field applied along and perpendicular to the rodlike crystals. For the applied field perpendicular to the rod, Hc 2(T ) is linear with a slope ∼-70 kOe/K. For field applied along the rod, the slope is about -120 kOe/K below 70 kOe. Above 70 kOe, the magnitude of the slope decreases to ∼-70 kOe/K. The electronic specific heat coefficient γ , just above Tc, is 73 mJ/mol K2; the Debye temperature ΘD is 220 K. The specific heat jump at the superconducting transition Δ C ∼2.2 γ Tc . Finally, for hydrostatic pressures up to ∼7 kbar, Tc decreases under pressure linearly at a rate of -0.034 K /kbar .
- Publication:
-
Physical Review B
- Pub Date:
- January 2015
- DOI:
- 10.1103/PhysRevB.91.020507
- arXiv:
- arXiv:1501.01554
- Bibcode:
- 2015PhRvB..91b0507K
- Keywords:
-
- 74.70.Xa;
- 74.25.Op;
- 74.25.Bt;
- 74.62.Fj;
- Mixed states critical fields and surface sheaths;
- Thermodynamic properties;
- Pressure effects;
- Condensed Matter - Superconductivity
- E-Print:
- figures are revised