Compute and sensing · Built and demonstrated
Quantum computers
Most of the largest processors are superconducting circuits, held near absolute zero.
The record behind quantum computers
Who is leading superconducting quantum computing · EPJ Quantum TechnologySuperconductors in quantum computers
A superconducting qubit is a resonant circuit made non-linear by a Josephson junction, so its energy levels are unevenly spaced and two of them can be addressed as a bit. It is built by lithography, and that is why this approach scaled before the others: the fabrication is a variant of something the semiconductor industry already knows how to do. The circuit has to be superconducting because resistance is decoherence, and it has to be very cold because the spacing between those levels corresponds to a temperature well under one kelvin.
What is stopping quantum computers
Nothing in this field is limited by a transition temperature. It is limited by loss at interfaces: the oxide on a surface, the substrate under a film, the residue at an etched edge. Coherence has improved by orders of magnitude over twenty years almost entirely through materials and process work on those interfaces, and that is the constraint class, not the conductor.
What a better material would change for quantum computers
Nothing here waits on a warmer superconductor. It waits on cleaner interfaces: a junction barrier reproducible across a wafer, a substrate that does not host two-level systems, an etch that leaves no lossy residue. Those are materials and process questions, and they are the questions that decide how large a processor gets.
Conductors used in quantum computers
Near quantum computers, in compute and sensing
SuperMatics is a platform infrastructure company for superconducting devices: software that finds the material and the process, lab work that makes and measures it, and pilot manufacturing with industrial partners.If you are working on something in this field and a material is what stands in the way, tell us about it.