Researchers at the University of New South Wales and a startup company, Silicon Quantum Computing, have released their Quantum Dot test results. The circuits use 10 carbon-based quantum points on a silicon substrate. The metal gate controls the flow of electrons. The paper is displayed Nature And you can download the whole paper from there.
What’s new about this is that the dots are precisely arranged to mimic an organic compound, polyacetylene. This allows researchers to model actual molecules. Simulation of molecules is important in the study of phases of extracellular matter, such as superconductivity. The interaction of particles inside, for example, a crystal structure is difficult to simulate using conventional methods. By creating a model using quantum techniques using the same scale and the same topology as the molecules in question, the simulation is simplified.
The SSH (Su-Schreffer-Heeger) model describes a single electron moving along a suspended tunnel coupling with a one-dimensional lattice. At least, that’s what the paper says and we have to believe it. It has been possible to create such a model for general systems, but for a “many body” problem, conventional computing just doesn’t work. Currently, the 10 dot model is accurate in terms of what a conventional computer can reasonably imitate. The team plans to create a 20 dot circuit that will allow for unique simulations that are not possible with classic computing technology.
The dots are created with a scanning tunneling microscope and have a Goldilocks effect relative to the size of the dots. If they are too small, energy levels are overwhelmed by phosphorus donors. Too large, and destabilizes the capacitive coupling system between points.
Admittedly, science on paper is quite dense. But the Methods section outlines what it takes to create something like this. You need silicon, high-temperature ovens and the ability to handle external gases and perform lithography. There is almost an IC fab in your basement. However, we wondered if anyone tried homebrewing chips using STM lithography as an alternative to optical lithography. It seems possible.
We can’t help with some more foreign gear, but if you want to create an STM it’s done. Although you can create Quantum Dot in your kitchen, we don’t think they will do the same.