50 citations · 222 across the 24 of their papers we have counts for
24 papers
Blocking transition of interface traps in MoS-on-SiO FETs
Santu Prasad Jana, Suraina Gupta, Anjan K. Gupta
Electrical conductivity with gate-sweep in a few layer MoS-on-SiO field-effect-transistor shows an abrupt reduction in hysteresis when cooled. The hysteresis and time depen…
A thermal model with AC Josephson effect for a shunted superconducting weak-link
Sourav Biswas, Anjan Kumar Gupta
Superconducting weak-link (WL), behaving like a Josephson junction (JJ), is fundamental to many superconducting devices such as nanoSQUIDs, single-photon detectors, and bolometers.…
Acoustic analog to multiple avoided-crossings in two coupled acoustic cavities
Arjit Kant Gupta, Anjan K. Gupta
A cylindrical pipe with closed ends and with a partition in-between exhibits acoustic modes in the two, thus formed, one-dimensional cavities at certain frequencies. A partial tran…
Magnetization Reversal Across Multiple Serial Barriers in a Single FeO Nanoparticle
Sagar Paul, Ganesh Kotagiri, Rini Ganguly +4
Depinning of nanoscale magnetic textures, such as domain walls, vortices and skyrmions, is of paramount importance for magnetic storage and information processing. We measure time-…
Stochastic resonance in thermally bistable Josephson weak-links and micro-SQUIDs
Sagar Paul, Ganesh Kotagiri, Rini Ganguly +3
Constriction-based Josephson weak-links display a thermal bi-stability between two states exhibiting zero and finite voltages. This manifests in experiments either as hysteresis in…
Elimination of thermal bistability in superconducting weak links by an inductive shunt
Sourav Biswas, Clemens B. Winkelmann, Hervé Courtois +3
The quantum phase-coherent behavior of superconducting weak links (WL) is often quenched in the finite voltage state, due to the heat dissipation and related thermal hysteresis. Th…
Josephson Coupling in the Dissipative State of a Thermally Hysteretic -SQUID
Sourav Biswas, Clemens B. Winkelmann, Hervé Courtois +1
Micron-sized superconducting interference devices (-SQUIDs) based on constrictions optimized for minimizing thermal runaway are shown to exhibit voltage oscillations with applie…
STM/S study of electronic inhomogeneity evolution with gate voltage in graphene: role of screening and charge-state of interface defects
Anil Kumar Singh, Anjan Kumar Gupta
Evolution of electronic inhomogeneities with back-gate voltage in graphene on SiO was studied using room temperature scanning tunneling microscopy and spectroscopy. The reversa…
Reversible control of interface-water induced carrier density in graphene-on-SiO by thermal cycling under gate-voltage
Anil Kumar Singh, Anjan Kumar Gupta
A reversible handle on graphene carrier density, other than the gate electric field, is desirable for memory applications of graphene. Our experiments show that the commonly observ…
Inhomogeneous screening of gate electric field by interface states in graphene FETs
Anil Kumar Singh, Anjan K. Gupta
The electronic states at graphene-SiO interface and their inhomogeneity was investigated using the back-gate-voltage dependence of local tunnel spectra acquired with a scanning…
Micron size superconducting quantum interference devices of lead (Pb)
Sagar Paul, Sourav Biswas, Anjan K. Gupta
Micron size superconducting quantum interference devices (-SQUID) of lead (Pb), for probing nano-magnetism, were fabricated and characterized. In order to get continuous Pb film…
Controlling hysteresis in superconducting constrictions with a resistive shunt
Nikhil Kumar, C. B. Winkelmann, Sourav Biswas +2
We demonstrate control of the thermal hysteresis in superconducting constrictions by adding a resistive shunt. In order to prevent thermal relaxation oscillations, the shunt resist…
Weakening of the spin density wave gap at low temperatures in SrFeAs single crystals
Anirban Dutta, Neeraj Kumar, A. Thamizhavel +1
We report on temperature dependent scanning tunneling microscopy and spectroscopy studies of undoped SrFeAs single crystals from 6 K to 292 K. Resistivity data show spi…
Reversibility of Superconducting Nb Weak Links Driven by the Proximity Effect in a Quantum Interference Device
Nikhil Kumar, T. Fournier, H. Courtois +2
We demonstrate the role of proximity effect in the thermal hysteresis of superconducting constrictions. From the analysis of successive thermal instabilities in the transport chara…
Evidence for topological surface states in metallic single crystals of Bi2Te3
Sourabh Barua, K. P. Rajeev, Anjan K. Gupta
Bi2Te3 is a member of a new class of materials known as topological insulators which are supposed to be insulating in the bulk and conducting on the surface. However experimental v…
Temperature and phase dynamics in superconducting weak-link
Anjan K. Gupta, Nikhil Kumar, Sourav Biswas
A time dependent thermal model for a superconducting constriction based weak-link (WL) is discussed for investigating the deterministic dynamics of its temperature and phase. A new…
Electronic inhomogeneities in the superconducting phase of CaFe1.96Ni0.04As2 single crystals
Anirban Dutta, Neeraj Kumar, A. Thamizhavel +1
Superconductivity in Iron-Arsenic based pnictides emerges in close proximity to an antiferromagnetic (AFM)ordered parent state and the AFM phase overlaps with superconducting (SC)…
Hysteresis in superconducting short weak links and -SQUIDs
Dibyendu Hazra, Lætitia Pascal, Hervé Courtois +1
Thermal hysteresis in a micron-size Superconducting Quantum Interference Device (-SQUID), with weak links as Josephson junctions, is an obstacle for improving its performance fo…
Tip induced doping effects in local tunnel spectra of graphene
Shyam K. Choudhury, Anjan K. Gupta
We report on tip induced doping in local tunnel spectra of single layer graphene (SLG) with tunable back-gate using room temperature scanning tunneling microscopy and spectroscopy…
Scanning Tunneling Microscopy and Spectroscopy study of charge inhomogeneities in bilayer Graphene
Shyam K. Choudhary, Anjan K. Gupta
We report room temperature scanning tunneling microscopy and spectroscopy study of bilayer graphene prepared by mechanical exfoliation on SiO/Si surface and electrically contac…
Evidence of mobile carriers with Charge Ordering gap in Epitaxial PrCaMnO Thin Films
Udai Raj Singh, S. Chaudhuri, Anirban Dutta +2
Epitaxial thin films of charge-ordered PrCaMnO have been studied using variable temperature Scanning tunneling microscopy and spectroscopy (STM/STS). The…
Polaronic Pseudogap in the Metallic Phase of LaCaMnO Thin Films
Udai Raj Singh, S. Chaudhuri, R. C. Budhani +1
The electronic density of states (DOS) of LaCaMnO(LCMO) strain free epitaxial thin films with an insulator-metal transition temperature (T) of 250 K…
Tunneling Study of the Charge-Ordering Gap on the Surface of LaPrCaMnO Thin Films
Udai Raj Singh, S. Chaudhuri, Shyam K. Choudhary +2
Variable temperature scanning tunneling microscopy/spectroscopy studies on (110) oriented epitaxial thin films of LaPrCaMnO are reported in the te…
Non-conservation of Density of States in BiSrCaCuO: Coexistence of Pseudogap and Superconducting gap
Anjan K. Gupta, K. -W. Ng
The tunneling spectra obtained within the ab-plane of BiSrCaCuO (Bi2212) for temperatures below and above the critical temperature (T) are analyzed. We find tha…