Quantum error correction definition
Quantum error correction is a method used in quantum computing to protect information from errors caused by noise and disturbances. When we say “noise and disturbances,” we mean unwanted interactions and environmental factors that can affect the units of information called qubits, leading to errors in calculations.
With quantum error correction, quantum computers can guarantee that their calculations are correct and can be trusted. They can perform advanced calculations without being greatly affected by errors or interference.
See also: post-quantum cryptography
How quantum error correction works
- The quantum information is encoded with additional qubits to make them more resilient.
- A set of operations, known as error detection codes, is applied to the encoded qubits to identify errors. These codes detect errors without directly measuring the encoded information, preserving the quantum state.
- Certain measurements are performed on the encoded qubits to obtain a “syndrome“ (information about the presence and location of errors).
- Based on the obtained information, the errors found are corrected, and the effects of the errors are reversed.
- After correcting the errors, the encoded qubits can be measured to get the final corrected quantum information. The redundant encoding and error correction ensures that the original data is recovered accurately, even in the presence of errors.
