Publications by authors named "R P Aloysius"

The interplay between superconducting fluctuations (SFs) and weak localization (WL) has been probed by temperature dependent resistance [()] and magnetoresistance (MR) measurements in two-dimensional disordered superconducting TiN thin films. Within a narrow range of temperature above transition temperature (), the coexistence of SF-mediated positive MR and WL-led negative MR in different ranges of magnetic fields and a crossover from positive MR to negative MR with an increase in temperature are reported herein. The crossover temperature coincides with a characteristic temperature () at which a resistance peak appears in the zero-field ().

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Granular superconductors are the common examples of experimentally accessible model systems which can be used to explore various fascinating quantum phenomena that are fundamentally important and technologically relevant. One such phenomenon is the occurrence of reentrant resistive states in granular superconductors. Here, we report the observation of multiple reentrant resistive states for a disordered TiN thin film in its temperature and magnetic field dependent resistance measurements, R(T) and R(B), respectively.

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We report on the superconducting properties and intermediate resistive steps (IRS) observed in the current-voltage characteristics (IVC) of tungsten meander (MW) structures fabricated using focused ion beam (FIB) technique. Three number of MWs were studied with individual wire widths of 240 nm, 640 nm and 850 nm with superconducting transition temperatures (TC) of 4.5 K, 4.

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Disorder induced phase slip (PS) events appearing in the current voltage characteristics (IVCs) are reported for two-dimensional TiN thin films produced by a robust substrate mediated nitridation technique. Here, high temperature annealing of Ti/SiN based metal/substrate assembly is the key to produce majority phase TiN accompanied by TiSi & elemental Si as minority phases. The method itself introduces different level of disorder intrinsically by tuning the amount of the non-superconducting minority phases that are controlled by annealing temperature (T) and the film thickness.

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Milling of 2D flakes is a simple method to fabricate nanomaterial of any desired shape and size. Inherently milling process can introduce the impurity or disorder which might show exotic quantum transport phenomenon when studied at the low temperature. Here we report temperature dependent weak antilocalization (WAL) effects in the sculpted nanowires of topological insulator in the presence of perpendicular magnetic field.

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