Page 22 - BE Book PESD 2021 22

10. Debjani Das Gupta, Physics and Applied Mathematics Unit, Indian Statistical
Institute, 203 Barrackpore Trunk Road, Kolkata-700 108, India
11. Ranjini Bhattacharya, Physics and Applied Mathematics Unit, Indian Statistical
Institute, 203 Barrackpore Trunk Road, Kolkata-700 108, India
12. Moumita Dey, Department of Physics, Adamas University, Barasat-Barrackpore
Road, Jagannathpur, Kolkata-700 126, India

A brief write up on the scope & justification of the Project and proposed work:

• Thermoelectric study for efficient energy conversion

Recent proposals have demonstrated that thermoelectric performance can significantly be
enhanced using nanoscale systems, compared to traditional bulk materials, although too limited
understanding is involved at nano-scale level. In view of this lack of understanding and its
scientific and technological importance, certainly there exists a great opportunity for new
discoveries. We are actively working in this project.

Collaborators: S. Chakraborty (ISI), M. Dey (Adamas University), Prof. K. Wakabayashi
(Kwansei Gakuin University, Japan),

• Spintronics in magnetic helix structure

Magnetic helix structure can be a role model for future spintronic devices. Utilizing the
advantage of constructing possible magnetic configurations, it is now possible to investigate
spin transport phenomena in different helical geometries with finite magnetic ordering. The
interplay between short-range and long-range hopping of electrons yields many non-trivial
features. Our analysis suggests that a high degree of spin polarization can be achieved in a
single stranded helical geometry, even in absence of environmental dephasing and longer-range
hopping.

Collaborator: S. Sarkar (ISI), D. Das Gupta (ISI)

• Topological states and localization phenomena

The examination of electronic spectrum of one-dimensional and quasi-one-dimensional
networks comprising of aperiodically varying site potentials might throw new light into the
behavior of electrons, both in the context of basic physics and possible technological
applications including DNA devices. It is well known that in 1D even for arbitrarily weak
disorder (almost) all the one-electron states are exponentially localized and one never
encounters mobility edge (ME). Considering a multi-stranded AAH network we examine how
to get ME and its possible tuning by regulating the AAH phase. Our analysis may lead to
important aspects of electronic localization in coupled AAH chains.

Collaborators: S. Roy (ISI), M. Saha (ISI), M. Patra (ISI), J. Majhi (ISI), Prof. S. Sil, (Visva-
Bharati University)

• Transport properties in presence of irradiation

In another context we focus on transport properties in AC driven quantum systems. Our
primary focus is to develop a suitable setup where transport current, circular current and

<< 16