Era of Quantum Computers

Dr. Parshotam S. Manhas
Humans have always fixated themselves on improving life across every spectrum and the role of technology has become inevitable.
The first revolution ‘Quantum 1.0’ has led to ubiquitous inventions such as lasers and semiconductor transistors. The second revolution termed ‘Quantum 2.0’ is currently underway with the goal of putting properties of quantum mechanics in the realms of computing. Quantum computing is a developing computer technology based on the principles of quantum-mechanical phenomena such as superposition and entanglement to perform computation and the devices that carry out such computations are known as quantum computers. Quantum computers are believed to be able to solve certain computational problems, such as integer factorization exceedingly faster than classical computers.
Classical computers can only encode information in bits of 1s or 0s. Quantum computers use quantum bits or qubits which represents electrons or photons and can be either 0s or 1s, or a superposition of both 0 and 1, thereby reducing data-crunching time. This superposition of qubits is what gives quantum computers their inherent parallelism. Entanglement, on the other hand, is a strong correlation between quantum particles and can generate pairs of qubits that exist in individual quantum states. Changing the state of one of the qubits in a pair will instantaneously change the state of the other one in a predictable way even if they are separated by a large distance. In essence, superposition and entanglement are two basic features of quantum physics that empowers quantum computers to handle operations at speeds exponentially higher than conventional computers and at much lesser energy consumption through use of quantum tunnelling.
A 30-qubit quantum computer would equal the processing power of a conventional computer that could run at 10 teraflops (trillions of floating-point operations per second). Today’s typical desktop computers run at speeds measured in gigaflops (billions of floating-point operations per second). Every day over 2.5 exabytes of data is produced which is equivalent to the content on 5 million laptops. Quantum computers will make it possible to process the big data that is generating in present era.
Quantum computers are getting increasing attention owing to the tremendous power of harnessing the counterintuitive physics of subatomic scales. Bringing a quantum computer online as soon as possible is the ultimate goal for the major industry leaders, even if they are approaching from different perspectives.
Today quantum computers have developed to the point of processors such as IBM’s 20-qubit first commercial quantum computer ‘the IBM Q System One’ unveiled at the beginning of 2019 and IBM’s new 53-qubit most powerful machine will be available for researchers and companies to run applications via the cloud. Amazon Web Services added a quantum computing service called Braket. Startup Rigetti Computing unveiled a 32-qubit machine and plans a 128-qubit quantum computer. Google has a 72-qubit device, but it hasn’t let outsiders run programs on it.
On October 23, 2019 Google announced that it had achieved ‘Quantum Supremacy’ meaning that they had used a 54-qubit processor named Sycamore to solve a particular problem in 200 seconds that a conventional computer would take tens of thousands of years to solve. IBM immediately contested this claim, saying that their conventional supercomputers could also solve the same problem in just 2.5 days and the goal of quantum supremacy has not been met. Though controversial, the announcement made by Google was one of the first steps towards realization of quantum computer.
Quantum computers will disrupt almost every industry and could contribute greatly in the fields of finance, military affairs, intelligence, environment, deep-space exploration, drug design and discovery, aerospace engineering, utilities like nuclear fusion, polymer design, artificial intelligence, big data search, and digital manufacturing. Quantum computers will not only solve all of life’s most complex problems and mysteries, but will soon empower all A.I. systems, acting as the brains of these super-human machines.
Teachers can use quantum computing as an object lesson to introduce high-level concepts e.g., the physics behind quantum machines offers avenue of exploration. Quantum computers will personalize higher education. The power and speed of quantum computing may best serve the individualized needs of the students in visualizing adaptive learning models. It constrains the space to make it more understandable and provides theoretical concepts a practical application. In broader picture, quantum computing will raise the bar in digital literacy. For students, quantum technologies are their future and they must have an early understanding of the fundamentals. IBM’s Qiskit, Q-CTRL’s tutorials, Microsoft’s Quantum Katas, QuTech’s Quantum Inspire are some of the online quantum computing platforms. An awesome future awaits for the education sector once the machines will come out of labs.
As quantum computers are extremely fast, their processing speeds could easily break the massively long strings of numbers used in today’s encryption software. It’s imperative to look at highly secure post-quantum algorithms that are quantum resistant and quantum cryptography technology such as quantum key distribution (QKD) that uses photons to distribute the cryptographic keys for secure encrypted communication. There are several algorithms already developed for quantum computers including Grover’s for searching an unstructured database and Shor’s for factoring large numbers.
Quantum computers are extremely difficult to build and program and expensive, to the tune of millions of dollars. The difficulty stems primarily from the challenge of working with fragile qubits and tricky phenomena like decoherence. Besides this, quantum computers are extremely sensitive to noise, faults, interference, and other environmental factors. Quantum computers take up a lot of space, require extremely low temperatures to operate, and are still very delicate.
The quest for large-scale, error-corrected quantum computers is in the offing. A few large companies and small start-ups have already started functioning non-error quantum computers composed of several tens of qubits, and some of these are even accessible to the public through the cloud. Quantum simulators are also making strides in fields varying from molecular energetics to many-body physics. Quantum computers based on semiconductor technology using the concept of quantum dots are yet another possibility. Quantum dots are man-made semiconductor nanoscale crystals that can transport electrons. Such a quantum system could be faster and provide more memory and has the potential to incorporate very large numbers of qubits.
Quantum computers, however, will never fully replace ‘classical’ computers that we use today. They won’t run web browsers, send emails, execute desktop publishing, or stream the latest video from Netflix. Quantum computers have the potential to revolutionize computation by making certain types of classically intractable problems solvable.
Quantum computers have come a long way from the early projects in the ’90s; but because of the finicky nature of quantum mechanics, it will take more time and money to move them completely out of the research labs and make available for mainstream use. The prudent course of action however is to be prepared well in advance from all perspectives. The era of quantum computers has in fact begun and should have far-reaching benefits to the entire world.