A new 'nanoscale hotspot' switch has finally given us the 'transistor' for zero-resistance electricity, the holy grail of supercomputing.
April 17, 2026
Original Paper
Nanoscale electrothermal-switch superconducting diode for electrically programmable superconducting circuits
arXiv · 2604.12313
The Takeaway
Superconductors allow electricity to flow with zero heat or loss, but they’ve been impossible to use for computing logic because we couldn't easily 'switch' the current on or off. These researchers created a superconducting diode that can be flipped, reversed, or shut down using a tiny, gate-controlled heat spot. This is the 'missing link' for building computers that are thousands of times faster than today’s best chips while using almost no power. It’s like going from vacuum tubes to silicon chips all over again, but for quantum-speed hardware. This makes programmable, scalable superconducting computers a matter of engineering rather than a pipe dream.
From the abstract
Superconducting diodes enable dissipationless directional transport, yet achieving electrical tunability and scalability remains a major challenge for circuit-level integration. Here, we demonstrate an electrothermal-switch superconducting diode in which a gate-controlled nanoscale hotspot dynamically breaks inversion symmetry in a superconducting nanowire. This mechanism gives rise to two coexisting nonreciprocal transport regimes-one associated with a nonreciprocal superconducting-to-normal tr