Quantum Current Metrology Section
One of the important and unresolved issues related to the quantum metrology is the quantum electrical metrological triangle which deals with the quantum electrical standards of voltage, resistance and current. In principle, the quantum metrological triangle (QMT) should allow these three electrical standards to be expressed in terms of fundamental constants and can be interrelated through Ohm's l aw. W e focus on the realization of quantum standard of current by using mainly quantum phase slip (QPS) based junctions and devices. The main objective is the observation of Shapiro steps in QPS junctions under microwave irradiation appropriately coupled to the device and the Optimization of the measurement conditions and scheme in order to achieve the desired accuracy in the measurement of the current steps towards a proto type device. There is already some success and the results are published in Sci. Rep. 5, 13459 (2015) and Sci. Rep. 6, 18689 (2015).
Another important activity is search for new superconductors. The program is supported by DAE-SRC Outstanding Investigator Award scheme and the in house budget from CSIR-NPL. Most of the superconducting materials starting from BCS type (MgCNi3, Bi3Ni, Nb and NbN etc.) to High T c cuprates including LSCO, YBCO, BISSCO, the Borides MgB2 and recently invented Fe based Pnictides (REFeAsO/F) and chalcogenides (FeTe/Se) are synthesized and studied in detail for their superconducting properties. The superconducting materials group is credited with starting of Fe based superconductors research in country [ Current Sci. 20, 95 (2008) ]. Recently, the group has contributed significantly to the discovery of BiS2 based new superconductors [ J. Am. Chem. Soc 134, 16504 (2012) ]. More recently, the non-centro-symmetric superconductors viz. BiPd [ SUST 29, 025008 (2016) & PRL117, 177001 (2016) ] and topological insulators superconductivity has been the passion of the group. Not only bulk but quality single crystals of pure and doped superconductors viz., Fe chalcogenides (FeTe/Se), Pd based PdTe and BiPd along with topological insulators (Bi 2 Te 3 , Bi 2 Se 3 with Cu/Nb intercalation) are grown and studied in the group. Over 15 Ph.D are yet awarded in last over a decade from superconducting materials activity. Several Awards including MRS medal, INSA Young Sci, Medal, MRSI-ICSC Prize, DAE-SRC Award, and APAM Fellow are won recently.
Head: Dr. V.P.S. Awana
Deputy Head: Dr. (Ms.) Sangeeta Sahoo
|Dr. V.P.S. Awana||4393||Principal Scientist|
|Dr. (Ms) Sangeeta Sahoo||5082||Sr. Scientist|
|Dr. Ajeet Kumar||5085||Scientist|