Quantum decoherence is the process by which a qubit loses its quantum properties (superposition and entanglement) due to unwanted interactions with its environment, effectively converting quantum information into classical noise.
Why it matters. Decoherence is the fundamental enemy of quantum computing. It is what makes quantum computation difficult: every interaction between a qubit and its surroundings (thermal photons, magnetic field fluctuations, charge noise, vibrations) degrades the quantum state. Decoherence is characterised by the relaxation time T1 and the coherence time T2 of the qubit. Reducing decoherence requires improvements at every level: better materials and fabrication (to reduce defects), better shielding and filtering (to block environmental noise), and better control electronics (to avoid introducing noise through the control lines themselves). Quantum error correction provides a way to compute despite decoherence, but only if the decoherence rate is below a threshold.
How it connects. The Qblox control stack is designed to minimize its own contribution to qubit decoherence. Ultra-low 1/f noise in baseband modules, high phase stability in RF modules, ground-loop elimination in the DC Cluster, and exceptional signal purity across all channels ensure that the electronics support rather than limit qubit coherence. Learn more about the Qblox Cluster.
