Coherence

Coherence

Coherence refers to the ability of quantum systems, such as qubits, to maintain their quantum states and evolve in a predictable manner over a specific period of time. It is a measure of how well a quantum system can maintain and manipulate the delicate superposition of quantum states.

In simpler terms, coherence is like the stability or integrity of a quantum system. It is crucial for performing accurate computations and taking advantage of the unique properties of quantum mechanics.

Coherence is often expressed as a coherence time, which quantifies the duration during which a quantum system can maintain its coherence. This coherence time is influenced by various factors, such as external environmental disturbances, noise, and the quality of the physical components used to implement quantum systems.

When coherence is lost, a quantum system undergoes a process called decoherence, where the quantum states become entangled or mixed with the surrounding environment. Decoherence inhibits the ability to perform precise quantum computations and can lead to errors.

Researchers in quantum computing aim to extend coherence times and develop methods to mitigate the effects of decoherence. This involves techniques such as error correction codes, physical isolation, and designing better control mechanisms.