Intel-backed boffins demo long-lived silicon qubit Bit by bit, the world gets closer to creating the quantum equivalent of a storage gate – a silicon-based qubit that can last long enough for general-purpose computing. If you want to use the superposition – the quantum property in which a gate can exist as 0 and 1 at the same time – for computation, it needs a usable “ …
The superconductor folks figured out a long time ago the link between isotope mass and Tc.
Unfortunately it seems that the process to enrich silicon is a lot more complex due to the lower mass, I am pretty sure that this will be a big problem unless these chips are made by the million and then simply selected by X-ray fluorescence (XRF) analysis in much the same way that flash chips are tested during wafer sorting and the bad areas mapped out.
I did read a fascinating article suggesting that "holistic" ie hole based qubits could be the next big thing (or not-thing) in QC research.
Hilarious that the absence of an electron can solve a nearly unsolvable problem yet people have known for decades that electron holes move much slower than electrons.
Maybe we should get a few botanists in at NASA, and nuclear physicists in the condensed matter laboratories for their "unusual" points of view?
Gate fidelity was measured at around 99 per cent, the paper says, “which is consistent with dephasing from the slowly evolving nuclear spins in the substrate.”
Does that mean that there is a window of stability* during which the gate fidelity is a constant 100%?
* Shorter than 0.4 milliseconds.
Probably not, by the time they get phones this advanced the cooling will be done on-chip using semiconductor lasers and a rubidium "Physics Package" or similar.
I read that Cool-X had a prototype that could get (in vacuum) down to -90C with a two stage micro-Peltier module but there are better units that can cool down to liquid nitrogen temperatures using thermionic cells based on nanopatterend caesium.
The actual amount of Cs in one of these is about the same as iridium in a phone screen so even if ruptured accidentally its not even as hazardous as a lithium cell.
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