Career

  • Senior Lecturer, Loughborough University, UK 2019-present
  • Lecturer (Vice-Chancellor Lectureship), Loughborough University, UK 2016  - 2019
  • Postdoctoral Research Associate, University of Cambridge, UK 2011 -2015
  • Junior Research Fellow, Wolfson College, University of Cambridge, UK 2013 -2015

Education

  • PhD in Materials Science, University of Cambridge, UK 2008 -2011 (Supervisor: Prof. Mark Blamire)
  • M.Tech in Materials Engineering, Indian Institute of Technology, Kanpur, India 2006 -2008
  • B.E. in Metallurgy and Materials Engineering, IIEST, Shibpur, India 2002 -2006

Research Grants

  • EPSRC Capital Award for Core Equipment 2019
  • British Council UK-India Education and Research Initiative Grant 2019 - 
  • Society for Promotion of Academic and Research Collaboration, India 2019 - 
  • EPSRC New Investigator Award, 2019 - 2021
  • EPSRC Capital Award emphasising support for Early Career Researchers 2018
  • EPSRC Overseas Travel Grant, 2018
  • UK-India Education and Research Initiative Thematic Partnership Grant, 2017 - 2020.
  • CALIBRE funding, Loughborough University, UK, 2016 - 2017.
  • Loughborough Strategic Grant, Loughborough University, UK, 2016.
  • Loughborough Strategic Grant, Loughborough University, UK, 2016.
  • Loughborough Start-up Grant, Loughborough University, UK,  2016. 

Awards & Fellowships

  • Vice Chancellor Lectureship, Loughborough University, UK, 2016-present.
  • Research Fellowship, Wolfson College, University of Cambridge, UK, 2013-2015.
  • Dr Manmohan Singh Scholarship (Prime Minister’s Scholarship, India), St. John’s College, University of Cambridge, UK, 2008-2011.
  • Overseas Research Student (ORS) award, University of Cambridge, UK, 2008-2011.
  • Honorary Cambridge Commonwealth Trust Scholar, UK, 2008-2011.
  • Best student awarded by Materials Engineering Department, IIT Kanpur, India, 2008.
  • Tata Steel Scholarship, India, 2005-2006.
  • Jawaharlal Nehru Centre for Advanced Scientific Research Summer Research Fellowship, India, 2004-2005.

Teaching

  • Module leader for Part C course Advanced Physics Laboratory 2017 - present
  • Module leader for Part A course Matter and Waves 2017 - 2019
  • Part A small group tutorials 2016, 2017

Professional Activities

Membership

  • Member of the EPSRC Peer Review College
  • Member of the Institute of Physics 
  • Editorial Board Member, Heliyon - Elsevier.
  • Member of the Governing Body, Wolfson College, Cambridge, UK, 2013-2015.

Journal Referee

Nano Letters, Communications Materials, Scientific Reports, Superconductor Science and Technology, Journal of Physics D: Applied Physics, Nanotechnology, APL Materials, Journal of Physics: Condensed Matter.

Administrative responsibilities

  • Juno and Equality and Diversity Coordinator 2020 - present
  • Postgraduate Programme Director 2018 - 2020
  • Postgraduate Admissions Tutor 2018 - 2020
  • Part B tutor and ERASMUS and Placements Coordinator 2017-2018

Superconducting spintronics

Conventional superconductors are formed of antiparallel spin-paired electrons (singlet Cooper pairs, ↑↓) with zero net spin while ferromagnets with aligned spins are the key to spin-based electronics (spintronics).

Recently, a synergy between superconductivity and spintronics has been achieved by creating spin triplet Cooper pairs with aligned spins (↑↑ ­­or ↓↓) at the interface between a superconductor and a ferromagnet. The net spin of the superconductivity, in principle, creates a bridge between spintronics and superconducting electronics (superconducting spintronics). 

In the last few years, we have demonstrated radically novel ways to generate and control triplet Cooper pairs in multilayer ferromagnetic Josephson junctions (Nature Communications 5, 4771, 2014Figure 1), ability of ferromagnets to filter triplet Cooper pairs (Nature Communications 5, 3048, 2014) and triplet superconducting spin switches (Physical Review B, 89, 140508(R), 2014).

Our recent work (Physical Review B, 98, 144516, 2018 Figure 2) has identified a unique way to dynamically detect triplets. It shows that our present understanding of the dynamics of the triplet superconducting state is limited and opens the possibility for new theoretical models to describe the dynamics.

Superconducting spintronics figure 1
Figure 1:(a) At high magnetic fields, the ferromagnetic (F) layers are parallel and the combined F-layer thickness is much greater than the coherence length of the singlet Cooper pairs; no supercurrent flows through the structure. (b) At zero or low magnetic fields, the inhomogeneous or non-collinear F'layers converts the spin-singley Cooper pairs in S in to equal spin-triplet Cooper pairs in F thus allowing a finite triplet supercurrent to flow through the structure.
Superconducting spintronics figure 2
Figure 2: Phase dynamics of triplet Josephson junctions can remarkably be reconstructed within the framework of the well-known resistively and capacitvely shunted junction model with renormalized parameters, possibly providing a novel way to dynamically detect triplets.

Spin-orbit coupling-driven superconducting spintronics

Superconducting spintronics, although attractive, has some serious challenges. The ↑↑ or ↓↓ triplet Cooper pairs are generated from ↑↓ singlet Cooper pairs by passing them through two ferromagnetic thin film (F1, F2) layers with non-collinear (ideally orthogonal) magnetisations. Maintaining non-collinear alignments is difficult, especially in nanoscale devices like Josephson junctions. Practical applications require a significantly simplified structure with fewer F layers and interfaces. 

The aim of this research theme is to demonstrate a radically different approach: generate and control triplet Cooper pairs by incorporating spin-orbit coupling (SOC) at the interface between a superconductor and a single homogeneous ferromagnet. This not only dramatically simplifies the structure, but opens an entirely new avenue in superconducting spintronics making it practically feasible. This builds on our recent results showing the controlled generation of triplet Cooper pairs in Nb/Pt/Co/Pt system (Physical Review B. 97, 184521, 2018Figure 1).   

Spin-orbit coupling-driven superconducting spintronics figure 1

Figure 1. Critical temperature difference ∆Tc calculated between Nb/Pt/Co/Pt and Nb/Co/Pt as a function of in-and out-of-plane fields H. Top row shows the (a) experimental and (b) simulated ∆Tc for in-plane fields. Corresponding out-of-plane (c) experimental and (d) simulated ∆Tc are shown in the bottom row. Without spin-orbit coupling, ∆Tc should be zero in both cases.

Novel electronic and magnetic states in pyrochlore iridates

The interplay of electron correlations, band topology and frustration inpyrochlore iridates (R2Ir2O7, R= rare earths) gives rise to unique correlated electronic and magnetic states. With a broader aim to design multifunctional materials for energy efficient ultralow dissipative devices, we will study how these effects could be controllably tuned in thin films and the possibility to induce novel phases by application of pressure and interface it with other materials with radically different order parameters (like superconductors). This work is in collaboration with Prof. Subham Majumdar's group at the Indian Association for the Cultivation of Science, Kolkata.

Diamond anvil cell and band gap diagram
On the left: Diamond anvil cell for high-pressure experiment. On the right: The band gap can in pyrochlore iridates can be tuned by applying hydrostatic pressure which will modify electronic transport properties of the iridates.
  1. César González-Ruano, Lina G. Johnsen, Diego Caso, Coriolan Tiusan, Michel Hehn, Niladri Banerjee, Jacob Linder, and Farkhad G. Aliev, 'Superconductivity-induced change in magnetic anisotropy in epitaxial ferromagnet-superconductor hybrids with spin-orbit interaction', Phys. Rev. B, 102, 020405(R) (2020).
  2. Johannes R. Eskilt, Morten Amundsen, Niladri Banerjee, and Jacob Linder, 'Long-ranged triplet supercurrent in a single in-plane ferromagnet with spin-orbit coupled contacts to superconductors', Phys. Rev. B, 100, 224519 (2019).
  3. Manjil DasAnupam BanerjeeNiladri Banerjeeand Subham Majumdar, 'Magnetic and transport studies in doped iridium pyrochlore oxides', AIP Conference Proceedings 2115, 030527 (2019)
  4. Lina G Johnsen, Niladri Banerjee and Jacob Linder, 'Magnetization reorientation due to the superconducting transition in heavy-metal heterostructures', Phys. Rev. B, 99, 134516 (2019).
  5. N. Banerjee*, 'A cool spin on supercomputers', Physics World, 32, 4, (2019). (See this edition of Physics World on the website)
  6. D. Massarotti, N. Banerjee*, R. Caruso, G. Rotoli, M. G. Blamire and F Tafuri, 'Electrodynamics of Josephson junctions containing strong ferromagnets', Phys. Rev. B, 98,144516 (2018).
  7. D. Karar, N. R. Bandyopadhyay, A. K. Pramanick, D. Acharyya, G. Conibeer, N. Banerjee, O. E. Kusmartseva and M. Ray, 'Quasi-Two-Dimensional Luminescent Silicon Nanosheets', J. Phys. Chem. C, 122 (33), pp 18912–18921 (2018).
  8. N. Banerjee*, Y. Zhu, J. A. Ouassou, N. A Stelmashenko, J. Linder and M. G. Blamire, ‘Controlling the superconducting transition by spin-orbit coupling’, Phys. Rev. B, 97, 184521 (2018). (See the news article in full here.)
  9. T. D. C. Higgs, S. Bonetti, H. Ohldag, N. Banerjee, X. L. Wang, A. Rosenberg, Z. Cai, J. H. Zhao, K. A. Moler, J. W. A. Robinson, ‘Magnetic coupling at ferromagnet rare earth/transition-metal interfaces: A comprehensive study’, Scientific Reports, 6:30092 (2016).
  10. N. Banerjee*, J. W. A. Robinson and M. G. Blamire, ‘Reversible control of triplet supercurrents in ferromagnetic Josephson junctions’, Nature Communications, 5:4771 (2014).
  11. X. L. Wang, A. Di Bernardo, N. Banerjee, A. Wells, F. S. Bergeret, M. G. Blamire, and J. W. A. Robinson, ‘Giant triplet proximity effect in superconducting pseudo spin valves with engineered anisotropy’, Phys. Rev. B (Rapid), 89, 140508(R) (2014).
  12. J. W. A. Robinson, N. Banerjee and M. G. Blamire, ‘Triplet pair correlations and non-monotonic supercurrent decay with Cr thickness in Nb/Cr/Fe/Nb Josephson devices’, Phys. Rev. B, 89, 104505 (2014).
  13. N. Banerjee, C. B. Smiet, R. G. J. Smits, A. Ozaeta, F. S. Bergeret, M. G. Blamire, and J. W. A. Robinson, ‘Evidence for spin-selectivity of triplet pairs in superconducting spin-valves’, Nature Communications, 5:3048, (2014).
    Press release: (Find out more on the Phys.org website). 
  14. M. G. Blamire, C. B. Smiet, N. Banerjee and J. W. A. Robinson, ‘Field modulation of the critical current in magnetic Josephson junctions’, Supercond. Sci. Technol, 26, 055017 (2013).
  15. N. Banerjee*, J. W. A. Robinson, A Aziz, M. Ali, B. J. Hickey and M. G. Blamire, ‘Band-structure- dependent nonlinear giant magnetoresistance in Ni1−xFedual spin valves’, Phys. Rev. B, 86, 134423 (2012).
  16. N. Banerjee, A Aziz, M. Ali, J. W. A. Robinson, B. J. Hickey and M. G. Blamire, ‘Thickness depen- dence and the role of spin transfer torque in nonlinear giant magnetoresistance of permalloy dual spin valves’, Phys. Rev. B, 82, 002046, (2010) (selected as editor’s suggestion) .
  17. Deepak, N. Banerjee and S. Seki, ‘Evidence of electron conductivity in polysilanes and its implica- tions in design of ultraviolet emitting devices’, J. Appl. Phys, 107, 124513 (2010).
  18. I. Pallecchi , L. Pellegrino , N. Banerjee, M. Cantoni, A. Gadaleta, A. S. Siri and D. Marre, ‘Cu2O as nonmagnetic semiconductor for spin transport in crystalline oxide electronics’, Phys. Rev. B, 85, 165311 (2010).
  19. A. M. H. R Hakimi, N. Banerjee, A. Aziz, J. W. A. Robinson, M. G. Blamire, ‘Measurement of spin diffusion length of ITO using current-perpendicular-to-plane giant magnetoresistance in spin valve junctions’, Appl. Phys. Lett, 96, 102514 (2010).
  20. N. Banerjee, B. Ghosh, Deepak and Sanjeev K. Shukla, ‘Investigation of photoluminescence degra- dation and OLED device of a new polysilane’, Proceedings of the XIV IWPSD (2007).

Corresponding author

Dr Niladri Banerjee (Group leader)‌

Postdoc

  • Dr Jhuma Sannigrahi

PhD students

  • Alkistis Zervou (jointly with Dr Joseph Betouras)
  • Ruta Sirvinskaite (jointly with Dr Michael Cropper)

Research assistant

  • Alistair Child

M.Phys students

  • Alex Bregazzi

Part C students

  • Humzah Javaid
  • Anna Solan‌

M.Sc students

  • Araminta Harrold