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Gopal Dixit (born 7 June 1983) is an Indian theoretical physicist and associate professor at the Department of Physics of the Indian Institute of Technology Bombay. His research lies at the interface of attosecond physics, physical chemistry, and ultrafast solid state physics in quantum materials, with applications ranging from atoms to nano-scale systems to polyatomic molecules of chemical and biological interest to valleytronics and lightwave electronics.

Gopal Dixit
Born	7 June 1983 Atarra, Banda, Uttar Pradesh, India
Citizenship	Indian
Alma mater	Ewing Christian College University of Allahabad Indian Institute of Technology Madras Indian Institute of Technology Kharagpur Technical University Munich Deutsches Elektronen-Synchrotron DESY Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie
Known for	Time-resolved x-ray diffraction, Attosecond Physics
Scientific career
Fields	Attosecond physics, Ultrafast laser spectroscopy
Institutions	IIT Bombay
Website	https://www.phy.iitb.ac.in/en/content/gopal-dixit

Biography

Born on 7 June 1983 at Atarra, Banda district of Uttar Pradesh, Gopal Dixit did his undergraduate studies at Ewing Christian College. After earning a bachelor degree in 2002, he moved to University of Allahabad to complete his master degree in physics in 2004.  During his PhD, he received DAAD fellowship to work in Technical University Munich from 2008 to 2010.  After receiving PhD in 2011 from Indian Institute of Technology Kharagpur, he joined Deutsches Elektronen-Synchrotron DESY for post-doctoral work. Subsequently, he joined Max-Born Institute Berlin in 2013 to continue his scientific work. Returning to India, he joined the Indian Institute of Technology, Bombay in December  2015 as an assistant professor, and holds the position of associate  professor since 2021. His scientific work has been covered by several media channels nationally and internationally. Rajya Sabha TV on the program Science monitor had telecasted his scientific work . He has received several national and international awards and fellowships. He has been recognised as one of the emerging leaders in 2021 around the globe by Journal of Physics B from Institute of Physics UK. He is a young editor of Ultrafast Science journal from  science partner journals, American Association for the Advancement of Science (AAAS) .

Scientific career

The early work of Gopal Dixit was focused on theoretical spectroscopy of atomic systems relevant for atomic clock and astrophysics . During his stay at DESY, he worked on imaging of electronic motion using time-resolved x-ray diffraction with the combination of high spatial (sub-angstrom) and temporal (sub-femtosecond) resolution. His work published in PNAS has genuinely shifted the paradigm in the field . It has been a long-held belief that when ultrashort X-ray pulses diffract from an electronic wave packet in the matter, they will take snapshots of the instantaneous electronic density of the wave packet. Dixit’s work has demonstrated that this is not always true. Using the quantum electrodynamic (QED) framework of light-matter interaction, he rigorously showed that X-ray images contain information both about the transition electron density and the electronic current. His work on the theory of time-resolved x-ray diffraction has been widely recognised, including in the MIT technology review and the news and views section of Nature Photonics .  During his stay in Berlin, he developed a novel and elegant approach for reconstructing the changing electronic density of active valence electrons from the total X-ray diffraction pattern. It is known that the x-ray diffraction pattern is dominated by the core, inner-valence, and inactive valence electrons. The fraction of the electronic charge in the chemical reaction is very low. The X-ray pattern is dominated by the core, inner-valence, and inactive valence electrons. He developed a reconstruction procedure that combines wide-angle and narrow-angle diffraction patterns. His approach brings out nearly effortlessly the desired contribution of the active valence electrons, for example, enabling one to distinguish synchronous from asynchronous electronic rearrangements, answering the decades-long debate on the nature of electronic rearrangements during a pericyclic reaction .  

Later at IIT Bombay, he demonstrated how time-resolved x-ray diffraction could retrieve electronic coherences and directly image electron currents in molecules undergoing photo-induced chemical dynamics with sub-angstrom spatial and sub-femtosecond temporal resolution .  Shifting the research interest,  he has investigated attosecond time-delays in photo-ionization triggered by spatially structured (e.g. vortex) beams. The idea was that an atom placed near the centre of the vortex would feel gradient fields and experience different selection rules, which leads a different centrifugal barrier and hence a different time delay in photo-emission . His suggested scheme has been verified independently by the experimentalist .

Another important direction of Gopal Dixit's research is the attosecond physics of the interaction between tailored light fields and solids, especially two-dimensional materials. He is currently working on high harmonic spectroscopy of attosecond electron dynamics in solids and on ultrafast valleytronics – the idea of storing and processing information with light in the valleys of the Brillouin zone at petahertz clock rates. His work in this direction is extremely successful – in particular, he has shown how one can use tailored light fields to achieve valley-selective excitation in pristine graphene – something thought to be impossible before . His work on light-induced valleytronics in graphene has been covered by FORBES , The Hindu , India Today , and nature India to name but a few.  He has also appeared in a talk show hosted by Stephen Ibaraki, a freelance reporter from Forbes and chairman of REDDS capital.