242 citations · 754 across the 27 of their papers we have counts for
27 papers
Observation of Intrinsic Anderson Localization in Few-Layer ReS
Shreya Paul, Pritam Das, Devarshi Chakrabarty +2
Electron localization phenomena are expected to play an important role in the transport properties of two-dimensional materials. Rhenium disulfide (ReS), with its narrow conduc…
Anisotropic exciton-polaritons reveal non-Hermitian topology in van der Waals materials
Devarshi Chakrabarty, Avijit Dhara, Pritam Das +3
Topological band theory has expanded into various domains in applied physics, offering significant potential for future technologies. Recent developments indicate that unique bulk…
Giant Resonance Raman Scattering via Anisotropic Excitons in ReS2
Pritam Das, Devarshi Chakrabarty, Neha Gill +1
Anisotropic two-dimensional (2D) semiconductors recently have emerged as a promising platform for polarization-controlled Raman amplification. In this study, we probe energy-depend…
Trion Engineered Multimodal Transistors in Two dimensional Bilayer Semiconductor Lateral Heterostructures
Baisali Kundu, Poulomi Chakrabarty, Avijit Dhara +9
Multimodal device operations are essential to advancing the integration of 2D semiconductors in electronics, photonics, information and quantum technology. Precise control over car…
Anisotropic exciton polariton pairs as a platform for PT-symmetric non-Hermitian physics
Devarshi Chakrabarty, Avijit Dhara, Pritam Das +3
Non-Hermitian systems with parity-time (PT) symmetry have been realized using optical constructs in the classical domain, leading to a plethora of non-intuitive phenomena. However,…
Zero-Threshold PT-Symmetric Polariton-Raman Laser
Avijit Dhara, Pritam Das, Devarshi Chakrabarty +3
Anisotropy endows topological aspects in optical systems and furnishes a platform to explore non-Hermitian physics, which can be harnessed for the polarization-selective amplificat…
Influence of the coherence of spectral domain interference of Fano resonance on the degree of polarization of light
Shyamal Guchhait, Devarshi Chakrabarty, Avijit Dhara +3
We show an intriguing connection between the coherence of spectral domain interference of two electromagnetic modes in Fano resonance and the resulting degree of polarization of li…
Probing spin dynamics of 2D excitons with twisted light
A. K. Pattanayak, P. Das, D. Chakrabarty +5
We propose a mechanism of intravalley spin-flip scattering in spin-valley coupled two dimensional systems by transferring momentum of light into exciton center of mass using optica…
A steady state approach for studying valley relaxation using optical vortex beam
Aswini Kumar Pattanayak, Pritam Das, Avijit Dhara +5
Spin-valley coupling in monolayer transition metal dichalcogenides gives rise to valley polarization and coherence effect, limited by intervalley scattering caused by exciton-phono…
Interfacial anisotropic exciton-polariton manifolds in ReS
Devarshi Chakrabarty, Avijit Dhara, Kritika Ghosh +4
Light-matter coupling in van der Waal's materials holds significant promise in realizing Bosonic condensation and superfluidity. The underlying semiconductor's crystal asymmetry, i…
Additional excitonic features and momentum-dark states in ReS2
Avijit Dhara, Devarshi Chakrabarty, Pritam Das +4
Unidirectional in-plane structural anisotropy in Rhenium-based transition metal dichalcogenides (TMDs) introduces a new class of 2-D materials, exhibiting anisotropic optical prope…
Observations on spatial variations of the Sr~{\sc i} 4607~Å~scattering polarization signals at different limb distances with ZIMPOL
Sajal Kumar Dhara, Emilia Capozzi, Daniel Gisler +5
The Sr~{\sc i} 4607~Å spectral line shows one of the strongest scattering polarization signals in the visible solar spectrum. The amplitude of this polarization signal is expected…
Spatial variations of the SrI 4607Åscattering polarization signals at subgranular scale observed with ZIMPOL at GREGOR telescope
Sajal Kumar Dhara, Emilia Capozzi, Daniel Gisler +5
Sr I 4607Åspectral line shows one of the strongest scattering polarization signals in the visible solar spectrum. The amplitudes of these signals are expected to vary at granular s…
Trigger of successive filament eruptions observed by SDO and STEREO
Sajal Kumar Dhara, Ravindra B., Pankaj Kumar +3
Using multi-wavelength observation from SDO and STEREO, we investigated the mechanism of two successive eruptions (F1 & F2) of a filament in active region NOAA 11444 on 27 march, 2…
Formation and eruption of a flux rope from the sigmoid active region NOAA 11719 and associated M6.5 flare: A multi-wavelength study
Bhuwan Joshi, Upendra Kushwaha, Astrid M. Veronig +3
We investigate the formation, activation and eruption of a flux rope from the sigmoid active region NOAA 11719 by analyzing E(UV), X-ray and radio measurements. During the pre-erup…
Fabry-Pérot based Narrow Band Imager for Solar Filament Observations
Sajal Kumar Dhara, B. Ravindra, Ravinder Kumar Banyal
We have recently developed a narrow band imager (NBI) using an air gap based Fabry-Pérot (FP) interferometer at the Indian Institute of Astrophysics, Bangalore. Narrow band imaging…
Carrier Transport in High Mobility InAs Nanowire Junctionless Transistors
Aniruddha Konar, John Mathew, Kaushik. Nayak +5
Ability to understand and model the performance limits of nanowire transistors is the key to design of next generation devices. Here, we report studies on high-mobility junction-le…
Observations of Photospheric Vortical Motions During the Early Stage of Filament Eruption
Sajal Kumar Dhara, B. Ravindra, Ravinder Kumar Banyal
Solar filaments/prominences exhibit rotational motion during different phases of their evolution from their formation to eruption. We have observed the rotational/vortical motion i…
Filament eruption in association with rotational motion near the filament footpoints
Sajal Kumar Dhara, B. Ravindra, Ravinder Kumar Banyal
The active region magnetic field surrounding the filament plays an important role in filament formation, their evolution and disruption. We investigated a filament eruption that oc…
High Q electromechanics with InAs nanowire quantum dots
Hari S. Solanki, Shamashis Sengupta, Sudipta Dubey +7
In this report, we study electromechanical properties of a suspended InAs nanowire (NW) resonator. At low temperatures, the NW acts as the island of a single electron transistor (S…
Field-effect modulation of conductance in VO2 nanobeam transistors with HfO2 as the gate dielectric
Shamashis Sengupta, Kevin Wang, Kai Liu +4
We study field-effect transistors realized from VO2 nanobeams with HfO2 as the gate dielectric. When heated up from low to high temperatures, VO2 undergoes an insulator-to-metal tr…
Tunable thermal conductivity in defect engineered nanowires at low temperatures
Sajal Dhara, Hari S. Solanki, Arvind Pawan R. +7
We measure the thermal conductivity () of individual InAs nanowires (NWs), and find that it is 3 orders of magnitude smaller than the bulk value in the temperature range of 10 t…
Facile fabrication of lateral nanowire wrap-gate devices with improved performance
Sajal Dhara, Shamashis Sengupta, Hari S. Solanki +5
We present a simple fabrication technique for lateral nanowire wrap-gate devices with high capacitive coupling and field-effect mobility. Our process uses e-beam lithography with a…
Nanoscale electromechanical resonators as probes of the charge density wave transition in NbSe
Shamashis Sengupta, Hari S. Solanki, Vibhor Singh +2
We study nanoelectromechanical resonators fabricated from suspended flakes of NbSe (thickness30-50 nm) to probe charge density wave (CDW) physics at nanoscale. Variation…