Speaker: Dr. Chandrima Banerjee, Assistant Professor, Department of Physics, IIT Kanpur.
Title: "Opto-Spintronics: Ultrafast Optical Control and Probing of Dynamic Magnetization"

Date: Friday, 27th 2026 - Time: 4 PM
Hi Tea & Coffee: 5 PM

Venue: CeNSE Seminar Hall

Abstract:

In this talk, I will discuss ultrafast non-equilibrium spin excitation in magnetic systems, 
which is a fascinating branch of opto-spintronics research. The motivation is to optically tune 
and probe the dynamic magnetic state at ultrashort timescales, which will be potentially useful 
for future magnetic storage and computation devices. The technique used is time resolved magneto 
optical Kerr effect spectroscopy with a dual pump scheme. This employs two consecutive ultrashort 
laser pulses to manipulate the magnetisation and subsequently examines it in the pump-probe manner. 
I will show all optical switching of magnetisation using femtosecond laser pulses in thin films of 
ferrimagnetic Heusler alloy Mn2RuxGa, which dynamically occurs in ~ 10 picoseconds. Finally, light matter 
interaction on picoseconds or sub-picosecond timescales not only provides insights into fundamental processes 
of nature, but also paves the way towards next-generation THz information processing and technology.

Biography:
Chandrima Banerjee is an Assistant Professor of Physics at IIT Kanpur. She earned her Master’s degree from 
IIT Delhi and completed her PhD in 2017 at S.N. Bose National Centre for Basic Sciences, India, under Prof. 
Anjan Barman, focusing on Brillouin light scattering of spin waves in ferromagnetic thin films and nanostructures.

As an Irish Research Council Postdoctoral Fellow at Trinity College Dublin (2018–2020), she discovered the fastest 
known all-optical magnetic switching in ferrimagnetic Heusler alloys. She then pursued her second postdoc at Technion, 
Israel (2020–2023), working on attosecond X-ray magnetic circular dichroism spectroscopy.

She joined IIT Kanpur in June 2023, where she is establishing her ultrafast optical spectroscopy lab 
and conducting micromagnetic simulations on chiral metamaterials for non-reciprocal magnonic propagation.


Host Faculty:  Prof. Dhavala Suri