Spin qubits: why semiconductor fabrication is quantum computing's fastest path to scale

An episode of the Thinking On Paper podcast, hosted by Mark Fielding and Jeremy Gilbertson, titled "Spin qubits: why semiconductor fabrication is quantum computing's fastest path to scale" was published on March 19, 2026 and runs 43 minutes.

March 19, 2026 ·43m · Thinking On Paper

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Summary

Spin qubits could scale quantum computing using the same semiconductor fabrication lines that print 50 billion transistors on an Nvidia chip. No new manufacturing paradigm required.Brandon Severin, Oxford PhD and founder of Conductor Quantum, joins Mark and Jeremy to explain why that matters. You need hundreds of reliable qubits for meaningful quantum computation. The industry has dozens. Spin qubits, built from modified transistors, controlled by classical voltages, no lasers, no vacuum, may be the most practical path to millions.This episode covers:Why qubit fidelity and coherence time determine what a quantum computer can actually doHow AI automates the calibration problem that makes human-controlled quantum scaling impossible - "you can't have a billion Brandons"Why trapped ions vs spin qubits is the wrong debateWhat Google's quantum algorithm result actually proved, and why it mattersWhy the physicists who understand semiconductor manufacturing may unlock use cases pure quantum researchers never reachThe two camps dividing the quantum industry: build one qubit at a time, or build for a millionAlso: quantum startup culture vs the AI boom, Brandon's Y Combinator experience, and why scaling quantum looks more like building a rocket ship than climbing a ladder.--Brandon Severin: https://www.conductorquantum.com/--⁠⁠Listen to every podcast⁠⁠Follow us on⁠ ⁠Instagram⁠⁠Follow us on⁠ ⁠X⁠⁠Follow Mark on⁠ ⁠LinkedIn⁠⁠Follow Jeremy on⁠ ⁠LinkedIn⁠⁠Read our⁠ ⁠Substack⁠⁠Email: ⁠[email protected]⁠--Timestamps(00:00) Introduction: spin qubits and the quantum scaling problem(03:47) Trapped ions vs spin qubits: fidelity, coherence, and tradeoffs(06:14) What qubit fidelity means and why it determines scaling limits(08:25) What is a spin qubit? Building from the transistor up(11:06) Semiconductor fabrication as quantum computing's manufacturing advantage(15:00) The quantum circus: superposition, measurement, Schrödinger's cat(17:17) Shuttling qubits — moving electrons across a chip(20:33) How AI automates quantum calibration (the control problem)(25:00) Quantum scaling vs AI scaling: the GPU parallel(29:08) Quantum startup culture and the AI generation gap(32:59) Building for a million qubits — rocket ships vs ladders(36:52) Why quantum is taking so long: talent, concentration, and meaning(39:43) What seems impossible now that will be routine in 20 years

Episode Description

Spin qubits could scale quantum computing using the same semiconductor fabrication lines that print 50 billion transistors on an Nvidia chip. No new manufacturing paradigm required.

Brandon Severin, Oxford PhD and founder of Conductor Quantum, joins Mark and Jeremy to explain why that matters.

You need hundreds of reliable qubits for meaningful quantum computation. The industry has dozens. Spin qubits, built from modified transistors, controlled by classical voltages, no lasers, no vacuum, may be the most practical path to millions.

This episode covers:

Why qubit fidelity and coherence time determine what a quantum computer can actually do
How AI automates the calibration problem that makes human-controlled quantum scaling impossible - "you can't have a billion Brandons"
Why trapped ions vs spin qubits is the wrong debate
What Google's quantum algorithm result actually proved, and why it matters
Why the physicists who understand semiconductor manufacturing may unlock use cases pure quantum researchers never reach
The two camps dividing the quantum industry: build one qubit at a time, or build for a million

Also: quantum startup culture vs the AI boom, Brandon's Y Combinator experience, and why scaling quantum looks more like building a rocket ship than climbing a ladder.

Brandon Severin: https://www.conductorquantum.com/