Source: HINDU

Disclaimer: Copyright infringement not intended.

Context

Google’s latest quantum processor Willow represents a major advancement in quantum computing addressing critical challenges and pushing the boundaries of computational power.

Quantum Computing

Quantum computing operates on quantum bits i.e. qubits unlike classical computing which relies on binary bits i.e. 0s and 1s.

The unique properties of qubits particularly superposition and entanglement allow quantum computers to process vast amounts of information simultaneously far surpassing the capabilities of classical computers.

Concepts in Quantum Computing

Quantum states are highly fragile leading to challenges such as qubit collapse and error accumulation during computations.

Willow's Advancements

Error Correction Protocols

Willow uses a surface code architecture where qubits are divided into data qubits and measurement qubits.

Errors in data qubits are detected and corrected via entanglement with measurement qubits without disrupting the quantum state.

Leakage errors caused by qubits entering unintended states are minimized.

Improved Coherence Time

Coherence time — the duration a qubit retains its state — is extended to 100 microseconds in Willow.

This enhancement achieved through error correction marks a significant improvement in the reliability of quantum computations.

Scalability and Error Rate

Willow employs 105 physical qubits in a 7x7 array with consistent reductions in error rates as qubit numbers increase.

This below-threshold capability demonstrates scalable error correction a critical step toward practical quantum computing.

Willow's Computational Achievement

Willow’s most notable feat was solving a random circuit sampling (RCS) problem — a computationally hard task — in mere minutes.

A classical supercomputer would require 10 septillion years to complete the same task.

This breakthrough illustrates the potential for quantum processors to outperform classical computers by unimaginable margins.

Potential applications

Drug discovery

Materials science

Climate modeling

Optimization problems

Sources:

HINDU