Melting of the Vortex Lattice through Intermediate Hexatic Fluid in an Thin Film

I Roy, S Dutta, AN Roy Choudhury, S Basistha… - Physical review …, 2019 - APS
The hexatic fluid refers to a phase in between a solid and a liquid that has short-range
positional order but quasi-long-range orientational order. In the celebrated theory of …

Structure and dynamics of a pinned vortex liquid in a superconducting thin film

R Duhan, S Sengupta, R Tomar, S Basistha, V Bagwe… - Physical Review B, 2023 - APS
We report the formation of a pinned vortex liquid spanning a very large region of the
magnetic field-temperature parameter space in a 5-nm-thick amorphous superconducting …

Disordering of the vortex lattice through successive destruction of positional and orientational order in a weakly pinned Co0.0075NbSe2 single crystal

S Chandra Ganguli, H Singh, G Saraswat, R Ganguly… - Scientific reports, 2015 - nature.com
The vortex lattice in a Type II superconductor provides a versatile model system to
investigate the order-disorder transition in a periodic medium in the presence of random …

Magnetic field induced emergent inhomogeneity in a superconducting film with weak and homogeneous disorder

R Ganguly, I Roy, A Banerjee, H Singh, A Ghosal… - Physical Review B, 2017 - APS
When a magnetic field is applied on a conventional type-II superconductor, the
superconducting state gets destroyed at the upper critical field, H c 2, where the normal …

Design and performance of an ultra-high vacuum spin-polarized scanning tunneling microscope operating at 30 mK and in a vector magnetic field

H von Allwörden, A Eich, EJ Knol… - Review of Scientific …, 2018 - pubs.aip.org
We describe the design and performance of a scanning tunneling microscope (STM) that
operates at a base temperature of 30 mK in a vector magnetic field. The cryogenics is based …

Extreme sensitivity of the vortex state in -MoGe films to radio-frequency electromagnetic perturbation

S Dutta, I Roy, S Mandal, J Jesudasan, V Bagwe… - Physical Review B, 2019 - APS
Recently, detailed real-space imaging using scanning tunneling spectroscopy of the vortex
lattice in a weakly pinned a-MoGe thin film revealed that the vortex lattice melts in two steps …

A 30 mK, 13.5 T scanning tunneling microscope with two independent tips

A Roychowdhury, MA Gubrud, R Dana… - Review of Scientific …, 2014 - pubs.aip.org
We describe the design, construction, and performance of an ultra-low temperature, high-
field scanning tunneling microscope (STM) with two independent tips. The STM is mounted …

Destruction of superconductivity through phase fluctuations in ultrathin -MoGe films

S Mandal, S Dutta, S Basistha, I Roy, J Jesudasan… - Physical Review B, 2020 - APS
Superconductivity occurs in metals when attractive interactions between electrons promote
the formation of Cooper pairs which get locked in a phase-coherent state, leading to …

Magnetic field induced transition from a vortex liquid to Bose metal in ultrathin -MoGe thin film

S Dutta, J Jesudasan, P Raychaudhuri - Physical Review B, 2022 - APS
We find transport and spectroscopic signatures that are consistent with a magnetic field
induced transition from a vortex liquid to Bose metal in a two-dimensional amorphous …

Collective flux pinning in hexatic vortex fluid in a-MoGe thin film

S Dutta, I Roy, S Basistha, S Mandal… - Journal of Physics …, 2019 - iopscience.iop.org
We investigate the magnetic field variation of the thermally activated flux flow resistivity, ρ
TAFF and flux flow critical current density, J c, in a weakly pinned thin film of the amorphous …