Quantum hardware roadmaps met the wiring problem at QCE26

This guide follows 19 hardware talks at IEEE Quantum Week 2026 in Toronto, from company keynotes to a single film of tantalum. Most of them asked how a machine of a few hundred qubits becomes a machine of a million. On the morning of Friday 18 September, in Hall G of the Metro Toronto Convention Centre, Matthias Troyer of Microsoft gave the quantum hardware crowd an unflattering picture of its own work. Seen from the engineering side, Troyer said, a quantum computer is mostly a classical machine joined to a fast network. The quantum calculation is a side effect of the classical signals sent down the cables to the qubits. Microsoft builds qubits too, which gave the remark its edge. Troyer was telling a room of qubit makers, whose quantum hardware roadmaps filled the week, to look harder at the cables. Nobody has yet agreed what a qubit should be made of. Superconducting circuits sit in fridges colder than deep space, ions and neutral atoms float in a vacuum held by electric fields or focused lasers, and photons run through glass at room temperature. Spin qubits hold single electrons in silicon. Each choice trades one strength for another, and the…