IBM’s l-couplers are long-range links between separate quantum processors, and IBM’s plan for 2027 and beyond depends on them. This guide covers what they are, what IBM has shown so far and how to read the fidelity figures that come with each announcement.
Category: Quantum Computing
Quantinuum’s 99.9995% Logical Fidelity: What the Record Measures
Quantinuum’s 99.9995% logical fidelity is about five logical errors per million error-correction cycles, measured on a distance-7 color code on Helios. This article covers what was measured, how the “10x” and “100x vs Google” claims compare, and what the result does not change.
Magic State Cultivation: What Google’s 40x Willow Result Means
Google reports that magic state cultivation cut errors 40x on its Willow processor. Here is what magic states are, why the T gate is a bottleneck, and what the result does and does not mean for RSA, ECDSA and crypto wallets.