Indian Lab Demonstrates Quantum Advantage Using IBM Quantum Processor

Syllabus: Science & Technology 

Context

• Scientists from BITS Pilani, in collaboration with IBM Quantum, have developed a quantum algorithm that demonstrated quantum advantage by simulating the behaviour of subatomic particles on a 120-qubit quantum processor.

Key Findings

• The quantum processor completed the simulation in 20 seconds. A classical computer required around two hours for the same calculation.
• The achievement has been recognised as “active” by the Quantum Advantage Tracker (QAT).
  • In the reference of the QAT “active” means that the claim of quantum advantage is currently valid and has not been disproved or overtaken by classical computing methods.
• Significance: It is the first quantum advantage claim from an Indian laboratory to receive active status.

What is Quantum Computing?

• Quantum computing refers to a new class of computers that use the principles of quantum mechanics rather than classical binary logic.
• Classical computers process information using bits (0 or 1), while quantum computers use qubits, which can exist in multiple states simultaneously.
• This capability allows quantum computers to perform certain calculations exponentially faster than conventional computers.

Principles of Quantum Computing

• Superposition: It allows a qubit to exist in multiple states simultaneously, enabling quantum computers to perform many calculations in parallel.
• Entanglement: It occurs when two or more qubits become strongly correlated, such that the state of one instantly determines the state of the other.
  • This property allows quantum computers to process and link information efficiently, helping solve complex problems faster.
• Decoherence: Decoherence refers to the loss of a qubit’s quantum state due to interaction with the environment (such as radiation or heat).
  • Preventing or delaying decoherence is a major challenge in building stable quantum computers.

What is Quantum Advantage?

• Quantum advantage refers to an information processing task performed more efficiently, cost-effectively, or accurately using a quantum computer than is known to be possible with classical computers alone.
• Quantum advantage is not universal; quantum computers are not faster for every type of calculation.

Quantum Advantage Tracker (QAT)

• The Quantum Advantage Tracker (QAT) is an open-source, platform-agnostic framework designed to collect, validate, and compare experimental results in the pursuit of quantum advantage. 
  • It verifies claims of quantum computing superiority. QAT requires users to match quantum results against classical methods to stop exaggerated claims.
• It uses three paths: observable estimations, variational problems, and classically verifiable problems. 
• Importance: Prevents exaggerated claims regarding quantum computing capabilities and provides credibility to genuine breakthroughs.

Challenges in Quantum Computing

• Lack of Indigenous Quantum Hardware: India currently depends on foreign quantum processors for advanced research.
• Quantum Error and Noise: Maintaining stable qubits for longer durations is difficult.
• Limited Real-World Applications: Most quantum demonstrations are still experimental and commercial applications require further technological maturity.

Source: TH