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We study the structural and bulk superconducting properties of self-flux grown PdBi2Te3 single crystal. Phase purity of as grown crystal is confirmed by Rietveld refinement of gently crushed powder XRD of the same. PdBi2Te3 crystallizes in rhombohedral structure with R-3 m space group along with small impurity of Bi. Scanning electron microscopy (SEM) images showed layered structure and the elemental analysis by energy dispersive X-ray analysis (EDAX) done on same confirmed the stoichiometry to be near to PdBi2Te3. Characteristic vibrational modes, viz., A11g, Eg2, and A21g, are clearly observed in Raman spectrum and are slightly shifted from that as in case of Bi2Te3. Bulk superconductivity is confirmed by FC and ZFC magnetization measurements (M-T) exhibiting diamagnetic transition with Tconset at around 6 K. M-H plots at different temperatures of 2 K, 2.5 K, 3 K, 3.5 K, 4 K, 4.5 K, 5 K, and 6 K showed clear opening of the loop right up to 6 K. Both M-T and M-H clearly establish the appearance of bulk type II superconductivity below 6 K in studied PdBi2Te3. The lower critical field Hc1 and upper critical field Hc2 are at 180 Oe at 4800 Oe, respectively, at 2 K for as grown PdBi2Te3 crystal. Other critical parameters of superconductivity such as coherence length, penetration depth and kappa parameter are also calculated. [ABSTRACT FROM AUTHOR]

We report an easy and versatile route for the synthesis of the parent phase of the newest superconducting wonder material, i.e., p-terphenyl. Doped p-terphenyl has recently shown superconductivity with transition temperature as high as 120 K. For crystal growth, the commercially available p-terphenyl powder is pelletized, encapsulated in an evacuated (10 Torr) quartz tube and subjected to high-temperature (260 C) melt followed by slow cooling at 5 C/h. A simple temperature-controlled heating furnace is used during the process. The obtained crystal is one piece, shiny, and plate like. Single crystal surface XRD (X-ray diffraction) showed unidirectional (00 l) lines, indicating that the crystal is grown along the c-direction. Powder XRD of the specimen showed that as grown p-terphenyl is crystallized in monoclinic structure with space group P2 /a space group, having lattice parameters a = 7.672 (2) Å, b = 5.772 (5) Å, and c = 13.526(3) Å and β = 91.484 (3). Scanning electron microscopy (SEM) pictures of the crystal showed clear layered slab-like growth without any visible contamination from oxygen. Characteristic reported Raman active modes related to C-C-C bending, C-H bending, C-C stretching, and C-H stretching vibrations are seen clearly for the studied p-terphenyl crystal. The physical properties of the crystal are yet underway. The short letter reports an easy and versatile crystal growth method for obtaining quality p-terphenyl. The same growth method may probably be applied to doped p-terphenyl and to subsequently achieve superconductivity to the tune of as high 120 K for the newest superconductivity wonder, i.e., high- T organic superconductor (HTOS). [ABSTRACT FROM AUTHOR]