Welcome to Superconductivity Lab,CG24

The phenomenon of superconductivity has captured the imagination of specialists and general public alike, ever since its discovery a hundred years ago. In our laboratory we focus on the study of unconventional and disordered superconductors using a combination of magneto-transport, tunneling (planar tunnel junctions and Scanning tunneling spectroscopy), Andreev reflection spectroscopy and penetration depth measurements. Using a variety of home-built systems we perform these measurements down to 300mK and up to magnetic fields of 12 Tesla. You will find more details of our work in our research pages

2022 Publications

Phase fluctuations in conventional superconductors

Pratap Raychaudhuri and Surajit Dutta

J. Phys.Condens. Matter 34 (2022) 083001


Superfluid density in conventional superconductors: from clean to strongly disordered

Surajit Dutta, Pratap Raychaudhuri, Sudhansu S Mandal,T V Ramakrishnan.

J. Phys.Condens. Matter 34 (2022) 335601


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 105 (14), L140503


Correlated carrier dynamics in a superconducting van der Waals heterostructure

Prakiran Baidya, Vivas Bagwe, Pratap Raychaudhuri, Aveek Bid

Applied Physics Letters 120 (18), 183101








2021 Publications

Andreev Reflections in NbN/Graphene Junctions under Large Magnetic Fields

Da Wang, Evan J. Telford, Avishai Benyamini, John Jesudasan, Pratap Raychaudhuri, Kenji Watanabe, Takashi Taniguchi, James Hone, Cory R. Dean and Abhay N.Pasupathy

Nano Lett. 2021, 21, 8229−8235




Nanoscale devices with superconducting electrodes to locally channel current in 3D Weyl semimetals

Biswajit Datta, Jaykumar Vaidya, Subhamoy Ghatak, Raghav Dhingra, Rajib Mondal, John Jesudasan, A. Thamizhavel, and Mandar M. Deshmukh

Appl. Phys. Lett. 119, 133501 (2021)




Transition from three- to two-dimensional Ising superconductivity in few-layer NbSe2 by proximity effect from van der Waals heterostacking

Prakiran Baidya, Divya Sahani, Hemanta Kumar Kundu, Simrandeep Kaur, Priya Tiwari, Vivas Bagwe, John Jesudasan, Awadhesh Narayan, Pratap Raychaudhuri and Aveek Bid.

PHYSICAL REVIEW B 104, 174510 (2021) .




Evidence of zero-point fluctuation of vortices in a very weakly pinned a-MoGe thin film

Surajit Dutta, Indranil Roy, John Jesudasan, Subir Sachdev, Pratap Raychaudhuri.

PHYSICAL REVIEW B 103, 214512 (2021).




Phase fluctuations in conventional superconductors

Pratap Raychaudhuri and Surajit Dutta.

J. Phys. Condens. Matter 34 (2022) 083001 .




Superconductivity in amorphous RexZr (x≈6) thin films

Surajit Dutta, Vivas Bagwe, Gorakhnath Chaurasiya, A. Thamizhavel, Rudheer Bapat, Pratap Raychaudhuri and Sangita Bose.

Journal of Alloys and Compounds. Volume 877, 5 October 2021, 160258. .






2020 Publications

Hall effect for Dirac electrons in graphene exposed to an Abrikosov flux lattice

Jonathan Schirmer , Ravi Kumar, Vivas Bagwe, Pratap Raychaudhuri, Takashi Taniguchi, Kenji Watanabe, C.-X. Liu, Anindya Das and J. K. Jain

EPL, 132 (2020) 37002 published online 29 December 2020




Coplanar cavity for strong coupling between photons and magnons in van der Waals antiferromagnet

Supriya Mandal, Lucky N. Kapoor, Sanat Ghosh, John Jesudasan, Soham Manni, A. Thamizhavel, Pratap Raychaudhuri, Vibhor Singh and Mandar M. Deshmukh.

Appl. Phys. Lett. 117, 263101 (2020) .




An inertial model of vortices to explain the extreme sensitivity of hexatic vortex fluid to low frequency ac excitation

Surajit Dutta and Pratap Raychaudhuri.

Physica C Volume 578, 15 November 2020, 1353740.




Destruction of superconductivity through phase fluctuations in ultrathin a-MoGe films

Soumyajit Mandal , Surajit Dutta, Somak Basistha, Indranil Roy, John Jesudasan, Vivas Bagwe , Lara Benfatto , Arumugam Thamizhavel and Pratap Raychaudhuri .

PHYSICAL REVIEW B 102, 060501(R) (2020).




AC measurement of the Nernst effect of thin films at low temperatures

Y. Wu, Surajit Dutta, John Jesudasan, A. Frydman and A. Roy.

Rev. Sci. Instrum. 91, 095112 (2020) .




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

Surajit Dutta, Indranil Roy, Somak Basistha, Soumyajit Mandal, John Jesudasan, Vivas Bagwe and Pratap Raychaudhuri

J. Phys. Condens. Matter 32, 075601 (2020).






2019 Publications

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


Surajit Dutta, Indranil Roy , Soumyajit Mandal, John Jesudasan, Vivas Bagwe, and Pratap Raychaudhuri

Phys. Rev. B 100, 214518 (2019). Published 30 December 2019.


Universal scaling behaviour near vortex-solid/glass to vortex-fluid transition in type-II superconductors in two and three dimensions.


Hemanta Kundu, John Jesudasan, Pratap Raychaudhuri, Subroto Mukerjee and Aveek Bid

EPL, 128 (2019) 27001. Published online 2 December 2019


Experimental test of strong pinning and creep in current-voltage characteristics of type-II superconductors.


Martin Buchacek, Zhi-Li Xiao, Surajit Dutta, Eva Y Andrei, Pratap Raychaudhuri, Vadim B Geshkenbein and Gianni Blatter

Phys. Rev. B 100, 224502 (2019) - Published 4 December 2019.


Effect of dimensionality on the vortex dynamics in a type-II superconductor.


Hemanta Kumar Kundu, Kazi Rafsanjani Amin, John Jesudasan, Pratap Raychaudhuri, Subroto Mukerjee, Aveek Bid

Phys. Rev. B 100, 174501 (2019).


Nonlinear I−V characteristics of two-dimensional superconductors: Berezinskii-Kosterlitz-Thouless physics versus inhomogeneity.


G. Venditti, J. Biscaras, S. Hurand, N. Bergeal, J. Lesueur, A. Dogra, R. C. Budhani, Mintu Mondal, John Jesudasan, Pratap Raychaudhuri, S. Caprara, and L. Benfatto

Phys. Rev. B 100, 064506 – Published 8 August 2019


Robust pseudogap across the magnetic field driven superconductor to insulator-like transition in strongly disordered NbN films.


Indranil Roy, Rini Ganguly, Harkirat Singh, and Pratap Raychaudhuri.

Eur. Phys. J. B (2019) 92: 49


Melting of the Vortex Lattice through Intermediate Hexatic Fluid in an a-MoGe Thin Film.


Indranil Roy, Surajit Dutta, Aditya N. Roy Choudhury, Somak Basistha, Ilaria Maccari, Soumyajit Mandal, John Jesudasan, Vivas Bagwe, Claudio Castellani, Lara Benfatto, and Pratap Raychaudhuri

Phys. Rev. Lett. 122, 047001 (2019).


Role of antisite disorder, electron-electron correlations, and a surface valence transition in the electronic structure of CeMnNi4.


Pampa Sadhukhan, Sunil Wilfred D'Souza, Vipin Kumar Singh, Rajendra Singh Dhaka, Andrei Gloskovskii, Sudesh Kumar Dhar, Pratap Raychaudhuri, Ashish Chainani, Aparna Chakrabarti, and Sudipta Roy Barman

Phys. Rev. B,99, 035102 (2019).


2018 Publications

Signatures of two-step impurity-mediated vortex lattice melting in Bose-Einstein condensates.


Thudiyangal Mithun, Somesh Chandra Ganguli, Pratap Raychaudhuri and Bishwajyoti Dey

EPL 123, 20004 (2018).


Inter-Landau-level Andreev Reflection at the Dirac Point in a Graphene Quantum Hall State Coupled to a NbSe2 Superconductor.


Manas Ranjan Sahu, Xin Liu, Arup Kumar Paul, Sourin Das, Pratap Raychaudhuri, J. K. Jain, and Anindya Das

PRL 121, 086809 (2018).








All our older and earlier publications can be viewed on this page




News 2020


Indranil Roy successfully defended his thesis titled " Study of Vortex Dynamics and Phase Transitions in Superconducting Thin Films."



Surajit Dutta was awarded the Best Poster Prize at the " EIH2020 - ELECTRONS AND IONS IN / ON HELIUM ", held at Centre for Nano Science and Engineering (CeNSE), Indian Institute of Science, Bangalore from 23 – 25 January 2020.

Poster Title " Extreme sensitivity of hexatic vortex fluid state in a-MoGe thin film to radio-frequency perturbation




News 2019


Indranil Roy won the 1st prize, also called S N Ghosal award, at the Young Physicists Colloquium 2019 organized by Indian Physical Society in Kolkata, Keeping up with his lab predecessors Goutam Sheet and Somesh Chandra Ganguli. (Two other former students Madhavi Chand and Mintu Mondal had gotten the 2nd and 3rd prize in their respective years.)


Surajit Dutta was awarded the Best Poster Prize at the " 2nd Annual Conference on Quantum Condensed Matter ", held at Indian Institute of Science, Bangalore from 8 – 10th July 2019.

Poster Title " Evidence of quantum vortex fluid in a-MoGe thin film.


News 2018


Indranil Roy was awarded for the Best Short Talk at the " National Conference On Quantum Condensed Matter (QMAT ", held at IISER MOHALI from 25th to 27th July 2018.

Talk Title " Observation of a hexatic liquid phase in vortex lattice of 2-D MoGe thin films."


Surajit Dutta was awarded the Best Poster Prize at the " National Conference On Quantum Condensed Matter (QMAT) ", held at IISER MOHALI from 25th to 27th July 2018.

Poster Title " Melting of vortex lattice in 2D MoGe thin films. "




All our older and earlier publications can be viewed on this page



Note :

TIFR announces the Jawaharlal Nehru Post-doctoral Visiting Scientists Scheme with very attractive salaries. Minimum one year postdoctoral experience required. Appointment term is for one year but can be extended by one more year.
Please e-mail for details.