Quantum Computers: The Dawn of a New Era
The topic of Quantum Computing evokes nostalgic memories, taking me back to June 2014 when as faculty at Amar Singh College I was in charge of organizing a two-day national seminar. The seminar titled “Towards New Horizons with Interplay between Physics & Computer Sciences” was first of its kind, focusing on cutting-edge scientific advances and technologies. The event covered Quantum Computing, Spintronics, Nanotechnology, Material Science, Crystal Engineering and more, across different technical sessions.
While our teams were scrutinizing/reviewing research papers, I noticed that there was not a single presentation on Quantum Computing. I saw this as a potential embarrassment. This gap needed to be filled. Quantum Computing, an emerging field even in contemporary times, and to prepare a presentation on this subject was undeniably a difficult endeavor. Amidst the tight schedules, I took the challenge. After two weeks of intensive research, delving into key 2014 articles from ‘Nature’, I successfully authored a paper titled “Advances in Quantum Computing—an Overview”. Presenting this pivotal work was a moment of relief, as it ensured that this essential topic was well-covered in the seminar.
Going back to the history of computing and the process of miniaturization, we saw the invention of Transistor in 1947 replacing bulky vacuum tubes, the development of Integrated Circuits (ICs) during 1950s/1960s with multiple components on a single chip, to the emergence of Microprocessors in 1970s, housing thousands of transistors. In 1965, Gordon E. Moore, the co-founder of Intel, made an observation that the ‘Number of Transistors on a chip doubles approximately after every 18/24 months’.
This observation became a law and over the last six decades, we witnessed rapid miniaturization of semiconductor circuitry with increasingly smaller, cheaper and more powerful computing devices, fuelling an information technology boom. Thus, from rudimentary chips with 32-transistors in 1964, we advanced to smart-phones, laptops etc containing billions of tiny transistors. Now, as the Microprocessors operate at nanoscale, the transistor size continues to shrink; we are approaching the physical limits imposed by the laws of Physics which threatens further progress in conventional computing.
This has driven the research towards new technologies with Quantum Computing emerging as promising field poised to revolutionize data processing.
Quantum Mechanics rules our microscopic world. At subatomic levels, the electrons, protons, photons etc., exhibit both particle and wave-like behavior and the outcomes are determined by probabilities rather than certainties. Quantum Computers leverage the principles of Quantum Mechanics, such as Superposition and Entanglement, to process information.
Unlike classical Computers, which use binary bits that exist in one of the two states: 0/1 to represent data, Quantum Computers use multiple states to process information using qubits. For example, while a classical 2-bit system can represent only one of the four states (00, 01, 10, 11) at a time, a quantum 2-qubit system can represent all four states simultaneously due to Superposition which allows a Quantum Computer to perform calculations on all these combinations simultaneously. Entanglement reveals complex correlations between qubits-the two particles are connected in such a way that the state of one instantly influences the state of another, regardless the distance between them. With 3-qubits of 0, 1’s we will have 8-possible states to process information on all these states simultaneously.
Thus a 3-qubit quantum computer will be 8-times faster than a 3-bit digital Computer. A 64-qubit Quantum Computer will be 264 faster than corresponding digital Computer. A 300-qubit Quantum Computer would be more powerful than 3-billion ordinary Computers or say all the Computers in the world.
The exponential growth to process information makes Quantum Computers exceptionally powerful to solve complex problems, much faster than Supercomputers. If all the qubits share information through entanglement, then it could race through myriad calculations in parallel. Through this parallelism, we can analyze massive complex data, equations, which includes creating virtual models to study Climate, Economy, Chemical processes in Drugs, Artificial Intelligence etc. Quantum Computers have the potential to revolutionize medical science. It can provide new insights into drug development, disease understanding and effective treatments.
The spy world has been looking Quantum Computing for its use in data encryption, code breaking and to read all secret information on the net and stop spies from tapping information from a data line. Thus, the technology also poses potential dangers and unpredictability, raising new ethical concerns, especially around data privacy and security. It may seem like fantasy, but the truth of Quantum Mechanics is undeniable. Quantum mechanics continues to be one of the most precise and successful scientific theories which plays a key role in all technological advancements.
The tech companies like IBM, Google, D-Wave, Intel, Microsoft, defense contractors etc have been actively advancing the hardware, software and algorithms for Quantum Computers. In 2016, IBM made a major advancement by offering access to its Quantum Computers via the cloud. IBM has since built over 70-Quantum Computers, with about 20-accessible through ‘’IBM Quantum Platform’’.
This allowed researchers/enthusiasts to explore the technology's real-world applications. It led to trillions of operations/experiments by users and publishing of 3,000 scientific papers thus, creating a foundation for future breakthroughs and turning the idea into a collaborative and evolving frontier. Even when there is no agreement on the best way to build a Quantum Computer, countries like US, China, Germany, Japan etc have invested in its research.
China at present is leading the research with massive funding of over $15 billion followed by EU, & U.S. In India many leading research institutions like IISc, TIFR, IITs, IISERs are carrying out research in Quantum Computing. India launched the National Quantum Mission (NQM) in April 2023 with the Union Cabinet approved a budget of Rs 6,000 crore. The Mission has established 04-Thematic Hubs with leading research institutions collaborating with global partners like IBM.
Despite claims and ongoing research, Quantum Computing is still in the research and development phase and is not yet ready for widespread everyday use. The biggest challenges facing Quantum Computers is to control qubits. Qubits can be 2-states of an Electron/Photon, Ion-energy levels; Superconducting Circuits, Quantum Dots etc and are controlled by using Lasers, EM-fields, Microwaves etc.
A Superposition of qubits is extremely delicate and prone to errors due to external interference. As, quantum particles cannot be observed without being altered; each time you read data of a qubit, it decoheres into a non-quantum state to become merely a bit, 0/1. The decoherence can be caused by temperature, vibration, acoustic waves, electric fields, or loss of photon. Thus particles used for calculations in a Quantum Computers must remain in isolation from their surroundings which will reduce the qubit error rate during operations.
There are reports that some Quantum Computers typically operate with a relatively small number of qubits in the range of 10 to 100, but to tackle complex problems and ensure error correction, they need to operate with a much larger number of qubits. With ongoing research focused at overcoming challenges such as improving qubit stability and reducing error rates, it is clear that quantum computing is still in its early stages.
The day may not be far off when Quantum Computers become a reality, but it hinges on innovative solutions and investments. As we move forward, Quantum Computing continues to be an exciting area of innovation and discovery. It holds an immense potential for creating a wide range of job opportunities for our youth across diverse fields. While the international race is underway, we have to wait and see which country will gain a quantum advantage.
The author is a College Principal
