H–T phase diagram and the nature of vortex-glass phase in a quasi-two-dimensional superconductor: Sn-metal layer sandwiched between graphene sheets

Abstract

The magnetic properties of a quasi two-dimensional superconductor, Sn-metal graphite (MG), are studied using DC and AC magnetic susceptibility. Sn-MG has a unique layered structure where Sn metal layer is sandwiched between adjacent graphene sheets. This compound undergoes a superconducting transition at T c = 3.75 K at H = 0. The H-T diagram of Sn-MG is similar to that of a quasi two-dimensional superconductors. The phase boundaries of vortex liquid, vortex glass, and vortex lattice phase merge into a multicritical point located at T * = 3.4 K and H * = 40 Oe. There are two irreversibility lines denoted by H gl (de Almeida-Thouless type) and H gl ′ (Gabay-Toulouse type), intersecting at T ′ 0 = 2.5 K and H ′ 0 = 160 Oe. The nature of slow dynamic and nonlinearity of the vortex glass phase is studied.

Sn/SnOx Core−Shell Nanospheres: Synthesis, Anode Performance in Li Ion Batteries, and Superconductivity

“…The critical field increases dramatically with decreasing size of the Sn core, in agreement with previous reports on Sn nanostructures. , Our measurements indicate that the critical field H C = 295 Oe of the 10 μm particles is similar to the bulk, value which is 309 Oe . This relatively small critical field can explain the shift of T C with applied magnetic field in larger particles (parts c and d of Figure ) …”

“…25 This relatively small critical field can explain the shift of T C with applied magnetic field in larger particles (parts c and d of Figure 6). 48 Although H C is similar to the bulk value in the microsized sample, in the smallest 30 nm sample it reaches the value of 8200 Oe, which is a factor of 30 higher than the bulk value. The increase of magnetization in the 30 nm sample with the field above 8200 Oe presumably reflects the paramagnetic contribution of the canted spins on nanoparticles surface.…”

Unusual butterfly-shaped magnetization signals and spin-glass-like behaviour in highly oriented pyrolytic graphite

“…5A,B (see ESI [21,22,24]. This observation highlights the existence of non-trivial spin arrangements in the sample and seems to exclude presence of superconductive transitions [23]. In particular, the magnetization M(T,H) irreversibility shown in Figs.5D and Fig.…”

Magnetism and superconductivity inMcTa2S2C(Suzuki1, Suzuki2, Walter3 2005Phys. Rev. BSelf Cite315600View full textAdd to dashboardCite

“…III, the exponent α for Co 0.33 Ta 2 S 2 C and Ni 0.33 Ta 2 S 2 C is on the same order as those for quasi 2D superconductors such as Pd-MG (metal graphite) (α = 1.43 ± 0.05 and T c = 3.82 ± 0.04 K) 31 and Sn-MG (α = 1.43 ± 0.05 and T c = 3.90 ± 0.08 K). 32 In these MG's, metal (Pd and Sn) layers, which are sandwiched between adjacent graphene sheets, exhibit superconductivity. Note that the exponent α of M c Ta 2 S 2 C is close to that (= 1.50) predicted from the de Almeida and Thouless 33 theory for spin glass behaviors.…”