India is starting work on building infrastructure and acquiring human resources in the first phase of its push to develop quantum computers.
Bengaluru: India has officially set out on its pursuit of a technology that scientists worldwide hail as the possible solution to some of the most complex problems, from global warming and hunger, to epidemics.
Over the next three years, India will lay the groundwork and set up initial infrastructure for research in the field of quantum computers, extremely powerful systems that, it is believed, will solve in hours or days the problems conventional computers could struggle with for billions of years.
This will be the first phase of a larger push in the field over the next decade. A budget of Rs 80 crore has been set aside for this phase.
The stage for this was set on 8 and 9 January, at the very first mission meeting of the Department of Science & Technology’s (DST’s) Rs 80 crore Quantum-Enabled Science & Technology (QuEST) programme, held at International Institute of Information Technology (IIIT)-Hyderabad.
The event was attended by nearly 50 delegates, most of them academics working in the area of quantum physics. Top science representatives of the government’s different research branches, including principal scientific adviser (PSA) to the government K. VijayRaghavan, ISRO chairman K. Sivan, and NITI Aayog member and former defence secretary Vijay Kumar Saraswat.
The idea of QuEST came about a year and a half ago, when the DST put out a call for proposals on projects related to the field of quantum computing. QuEST falls under the Interdisciplinary Cyber Physical Systems (ICPS) division of the DST.
A total of 130 proposals were received by the last date for submissions, 31 December 2017, from teams representing institutions like IIT Bombay, IIT Madras, Indian Institute of Science Education & Research (IISER) Mohali, Tata Institute of Fundamental Reseach (TIFR, Mumbai), Indian Institute of Science (IISc, Bengaluru), among others.
A scientific review committee then shortlisted 51 proposals, which were presented before a panel of eight senior officials, including Saraswat and VijayRaghavan.
“QuEST is aimed at considerably ramping up research and development activities in this emerging field that promises to grow important both strategically and economically,” VijayRaghavan told ThePrint.
“…It will ensure that the nation reaches, within a span of 10 years, the goal of achieving the technical capacity to build quantum computers and communications systems comparable with the best in the world, and hence earn a leadership role,” he added.
The first phase of the project, centred on building infrastructure and acquiring human resources, was the subject of discussions at the two-day meeting in Hyderabad.
It would see researchers develop basic physical and computation structures such as logic gates, light sources, sensors, imaging devices, clocks, and more, all in quantum states. The focus would be on quantum metrology (improved precision in measurements) and sensors.
“We are trying to build quantum computers in the long run,” said Kasturi Saha, one of the researchers whose project proposal has been finalised. “But first, we need to lay the groundwork to enable work in quantum mechanics in India.”
“We don’t have a lot of people working in this area, as the subject itself is new on the world platform, barely 10 to 20 years old,” said Rajamani Vijayaraghavan of TIFR, Mumbai. “There’s only a handful. So now we focus on not just helping them perform better research, but also bringing in newer people into the field.”
Phase 2 will see an effort to match international standards.
What is quantum computing?
Quantum mechanics (QM) — also called quantum theory or quantum physics — deals with forces that operate in the atomic and subatomic scales.
At these levels, all objects act as both particles and waves, and there is a general reduction in precision owing to uncertainty.
QM as a field was born under 100 years ago, during the times of Einstein, Heisenberg and Schrödinger, when the structure of the atom could not be explained by mechanical physics.
Today, we know more about protons, electrons, neutrons, and photons than ever before, and QM has applications in numerous fields.
It has enabled us to understand physical phenomena such as superconductivity (100 per cent conductivity) and DNA (the hereditary material in organisms, including humans).
It is used in semiconductors, lasers, Blu-ray, transistors, mobile phones, USB drives, MRI, electron microscopes, and even the basic light switch.
It has also brought about bizarre experiments — thought and real — such as the famous Schrödinger’s Cat experiment, being in two places at once, and having signals between particles travelling at 10,000 times the speed of light.
Full-fledged quantum computers do not exist yet, but several countries have built prototypes, with the United States, China and the Netherlands in the lead.
“What we have today are just toy computers that demonstrate that the idea works,” said Vijayaraghavan of TIFR. “But they aren’t powerful enough to show their superiority over conventional computers.”
How quantum computers work
Instead of using ‘bits’ like computers of today do, quantum systems would use ‘quantum bits’ or ‘qubits’.
The qubit is the basic unit of quantum computing and the subatomic equivalent of the binary system comprising 0s and 1s that we use today.
It uses binary properties of particles, electron spin (up and down), photon polarisation (positive and negative), etc, but, much like Schrödinger’s cat, can actually be in both states simultaneously, a phenomenon called superposition.
Furthermore, physicists have observed that when one particle is observed, it seems to affect the state of the completely different, opposite particle in a phenomenon called entanglement. This is the basis of quantum computing and communication.
The approved projects are categorised into four broad themes:
Theme 1: Quantum information technologies with photonic devices
This theme is most familiar and utilises India’s existing expertise on photonics (science of light generation and manipulation) and quantum optics (interaction of light with matter) to develop communication systems.
Projects under this theme will work with the ability to control and manipulate photons. This is the only non-quantum computing theme.
“This is primarily quantum communication,” said R. Vijayaraghavan. “Quantum mechanics will be used to transfer data securely, the way China sent information to space.”
Initial results will see setting up of communication links over short distances on the ground, before moving on to longer ones, and, eventually, even space.
Theme 2: Quantum information technologies with nitrogen vacancy and nuclear magnetic resonance (NMR)
The focus of theme 2 is using spin states in diamonds and performing quantum computation through NMR, which is described as “an analytical chemistry technique used… for determining the content and purity of a sample as well as its molecular structure”.
“A diamond is made up of a lattice of carbon atoms,” explained Saha, who is a co-coordinator for the theme, cited in nine proposals.
“When one carbon is replaced with a nitrogen atom along with a missing carbon atom near it, it creates a nitrogen vacancy (NV) centre,” said Saha.
“A diamond in NV centre enables electron spin manipulation using light and other forms of energy,” she added.
The techniques used will be of the NMR kind, and this is the only theme where work can be performed and results seen at room temperature. Others require cooling.
Saha’s project, for which she is the principal investigator, involves creating integrated hybrid structures that can capture photons.
“Nitrogen and silicon vacancy centres are efficient single-photon sources,” she explained. “If we want to harness a photon’s energy, we need to guide it to a specific place. A single photon source is at the heart of quantum computing.”
Theme 3: Quantum information technologies with ion-trap and optical-lattice devices
Individual atoms and ions trapped in various configurations, and cooled down to temperatures very close to absolute zero, will be used to build quantum computers and quantum simulators.
An ion trap is a combination of electric or magnetic fields used to capture charged particles. Qubits are then stored in stable states of each ion, and information can be transmitted between them. Ion traps are expected to be more scalable than any other form of quantum computing.
Theme 4: Quantum information technologies with superconducting and quantum-dot devices
This theme will utilise solid-state technology and is expected to help develop chip-based quantum computers operating at temperatures close to absolute zero (-273.14 degree Celsius). One approach uses superconducting thin-film devices to make quantum bits, while the second uses the spin of isolated electrons on a silicon chip.
Superconductors consist of a number of pairs of electrons that function as one and transmit information. Research in superconducting quantum computing is popular and already underway by IBM, Intel, Google and Microsoft.
India’s first quantum computer?
Phase 1 will see a lot of young project members working to build prototype quantum computers and sensors that are of 1 to 4 qubits.
“We would also like to make arrays of qubit registers in the future and scale up,” said Saha. The most powerful quantum computer chip we have today was built by Google last year, at 72 qubits.
“In the immediate future, we would be heavily advertising for PhD applications and research in this area to develop the basics first,” Saha added.
A dedicated website is expected soon as well, most likely under the DST banner.
Currently, QuEST is being funded by the DST, which has put in Rs 80 crore for Phase 1. After three years, the Defence Research and Development Organisation (DRDO), the Indian Space Research Organisation (ISRO), and the Department of Atomic Energy (DAE) are expected to jointly fund Phase 2 with Rs 300 crore.
“DRDO, ISRO and DAE will also have major roles in this synergy effort, each investing in a similar way in focus areas of their core interest,” explained VijayRaghavan.
“These efforts will greatly amplify our work in quantum communication and in building quantum computers,” he added.