Dr Aditi Sen De, a physicist with the Harish Chandra Research Institute, Prayagraj, has won the 2023 GD Birla Award for Scientific Excellence. The award, given annually by the KK Birla Foundation since 1991, recognises outstanding contributions by Indian scientists who are under the age of 50 and living and working in India.
De, who will turn 50 later this year, is the 33rd scientist, and the first woman, to receive the award. A statement from the KK Birla Foundation mentions her outstanding contribution to the development of quantum technologies. At the Harish Chandra Research Institute, she is a professor in the quantum information and computation (QIC) group.
QIC is a field that can revolutionise modern technology once its potential is tapped. In essence, it seeks to put the mysterious phenomena of quantum mechanics to practical use in fields such as computing, communication, sensing, and simulation.
“It is a science at the crossroads of physics, computer science, mathematics, and information theory, and can potentially revolutionise the future of communication and computational technologies,” De said.
The quantum world
Quantum physics appears mysterious because what happens in that world defies what we intuitively take as being natural. At the subatomic level, where the laws of classical physics cease to apply, a particle can occur in two states at the same time (superposition) while properties of one particle can be dictated by the properties of another (entanglement), no matter how far apart they are.
While quantum physics is something to study and wonder at, quantum information science looks at putting these properties to practical use. One of the most widely followed targets is the quantum computer, with speed and storage far beyond that of a classical computer. This depends on superposition: a quantum bit (qubit) of information can simultaneously have two identities, so that more and more qubits would store exponentially higher and higher amounts of information.
“Quantum information and computation is one of the most fascinating fields of research around the world,” De said.
She broadly classified quantum technologies into two categories — quantum computers and quantum communication devices. By exploiting quantum mechanical laws, communication schemes (with or without security) can be enhanced, sometimes even qualitatively, she said. Here, quantum entanglement comes into play. Other potential quantum devices include quantum sensors, and quantum thermal machines such as batteries and refrigerators.
“In this respect, I should also mention the National Quantum Mission which was declared by the Government of India to involve more scientists and industrialists to build quantum devices,” De said.
De’s work
De, an MSc in applied mathematics from Calcutta University, went on to do her PhD in physics at the University of Gadansk, Poland, in the early 2000s. Her thesis was on the subject that she is identified with today: ‘Manipuations of quantum physics and their nonclassical applications’.
This was at a time when the world was just waking up to the potential of quantum mechanics. “I started my career around 2000 and so at the time, it was in the initial phase. For example, point-to-point communication [between a single sender and a single receiver] had very limited applications. Several quantum communication protocols were discovered around the 1990s or later, typically dealing with a single sender and a single receiver,” De said.
Among other things, she is working on building a quantum communication network, a thriving area of research. The statement mentions her innovative concepts for such networks as well as her ideas for quantum batteries and quantum refrigerators.
“Our recent works include two proposals for quantum networks (or quantum internet (internet based on quantum physics),” she said.
“Apart from that, I am also working on the design of quantum thermal machines [such as batteries and refrigerators], quantum cryptographic networks involving several senders and receivers, and the characterisation of resources necessary for effective implementations of quantum communication and quantum algorithms. Another important direction that I am working on is to find suitable quantum systems in which quantum computers can be built.”
De won the prestigious Shanti Swarup Bhatnagar prize (2018), given to researchers under the age of 45, and the Buti Foundation Award (2012) for theoretical physics. She is a fellow of the Indian National Science Academy as well as the Indian Academy of Sciences. She is married to Ujjwal De, a physicist at the same institute.
