Quantum Computing

Table of Contents

Context: Researchers at Google Quantum AI demonstrated that a certain class of mathematical problems can only be solved by quantum computers, not classical computers.

What is Quantum Computing?

Quantum computing harnesses the laws of quantum mechanics to solve problems too complex for classical computers.
Unlike classical computing, which uses bits that can only be in one of two states (0 or 1), quantum computing uses quantum bits (qubits) that can be in multiple states at once.
This allows quantum computers to perform certain types of calculations faster than classical computers, and to solve problems that are difficult or impossible for classical computers to solve.

Properties of Quantum Computing:
- Superimposition: Superposition is the ability of a Quantum Computing system to be in multiple states simultaneously.
- Entanglement: It is the state where two systems are so strongly correlated that getting information about one system will give immediate information about the other, even if they are far apart.
- Interference: Interference can control quantum states and amplify the signals that go towards the right answer, while signals that are leading to the wrong answer are cancelled.

Benefits of Quantum Computers Over Classical Computers

Quantum speedup: Compared to classical computers, including super computers, Quantum Computing can process information faster.
- In 2019, Google announced that they have achieved ‘quantum supremacy’, in which a computer harnessing the properties of sub-atomic particles did a far better job of solving a problem than the world’s most powerful supercomputer.
Parallelism: With n qubits, a quantum computer can represent 2^n states simultaneously. This parallelism allows quantum computers to explore multiple possible solutions simultaneously, which can be advantageous for certain optimization and search problems.
Solving Hard Problems: Quantum computers have the potential to solve problems that are currently intractable for classical computers.
Higher privacy: The security of Quantum Computing is very high. Quantum Computing are difficult to be hacked due to their use of qubits.

Concerns Associated with Quantum Computing

Higher cost: The cost of setting of Quantum Computing system is high.
Temperature control: Quantum computers dissipate high heat and consume high amount of electric power. They require low temperature for operation.
High error rate: The error rate of Quantum Computing is high in comparison to error rate of conventional computers.
Sensitivity to Environment: Quantum technology is highly sensitive to environmental interference, such as temperature changes, magnetic fields, and vibrations.
- Qubits are easily disrupted by their surroundings which can cause them to lose their quantum properties and make mistakes in calculations.
Limited Control: It is difficult to control and manipulate quantum systems. Quantum-powered AI could create unintended consequences.

Initiatives taken by the government

National Quantum Mission (NQM)	In April 2023, the Union Cabinet approved the ₹6,003 crore National Quantum Mission (NQM) that will fund research and development of quantum computing technology and associated applications. The mission will be implemented by the Department of Science & Technology (DST) under the Ministry of Science & Technology from 2023 to 2031. Key feature of the NQM: The new mission targets developing intermediate scale quantum computers with 50-1000 physical qubits in 8 years in various platforms like superconducting and photonic technology. Satellite based secure quantum communications between ground stations over a range of 2000 kilometres within India, long distance secure quantum communications with other countries, inter-city quantum key distribution over 2000 km as well as multi-node Quantum network with quantum memories are also some of the deliverables of the Mission. The mission will help develop magnetometers with high sensitivity in atomic systems and Atomic Clocks for precision timing, communications and navigation. It will also support design and synthesis of quantum materials such as superconductors, novel semiconductor structures and topological materials for fabrication of quantum devices. Four Thematic Hubs (T-Hubs) will be set up in top academic and National R&D institutes on the domains – Quantum Computing, Quantum Communication, Quantum Sensing & Metrology and Quantum Materials & Devices. The hubs which will promote R&D in areas that are mandated to them.
Quantum-Enabled Science and Technology (QuEST)	Department of Science and Technology (DST) will invest to develop infrastructure and facilitate research in the field of quantum technologies.
Quantum Frontier mission	The Prime Minister’s Science, Technology and Innovation Advisory Council (PM-STIAC) will promote understanding and control of quantum mechanical systems.
Quantum Computer Simulator Toolkit (QSim)	This will help researchers and students to write and debug Quantum Code that is necessary for developing Quantum Algorithms and carry out research in the field.
I-HUB QTF	DST and research groups from IISER have launched I-HUB Quantum Technology Foundation (I-HUB QTF) to develop quantum technology.
Quantum Computing Applications Lab	Ministry of Electronics and Information Technology (MeitY) has collaborated with Amazon Web Services (AWS) to establish a to facilitate quantum computing-led research and development.