Quantum Computer Possible From Silicon Fab

Cash Mitchell writes: "This article from the EE Times says 'Researchers at the University of Wisconsin in Madison claim to have created the world's first successful simulation of a quantum-computer architecture that uses existing silicon fabrication techniques.... With existing fabrication techniques, the team estimates that a million-quantum-dot computer (1,024 x 1,024 array) could be built today and operated in the megahertz range.'"

Comments

Re:So, what can a million qubits calculate?

[Misanthropic Lycanth]

Quantum computer science is still in its infancy. There are some algorithms out there which operate much quicker than their classical counterparts (e.g. factoring, searching). There are others that are impossible. For instance, it is impossible to copy a qubit.

This book is pretty good. It's used at my university to teach an intro course in quantum computing.

For the physics-savvy

[carambola5]

I truly take pride in this discovery... mostly because I attend UW. But I suppose a love of physics helps in that area, too.

Anyways, here's a somewhat technical article regarding the research (PDF).

Oh, and "On Wisconsin!"

Re:Several thousand qubits is enough...

[Uller-RM]

It needs 2n + 1 qubits; you start with a superposition, raise it to a power, then measure the result, collapsing the first superposition into a subset of logarithms. The discrete log step is the clincher: once you know the number has a log, you can just perform a Fourier transform on the superposition of logs, and the rest is all number theory.

And yes, you realistically need a LOT of extra qubits for error-correcting codes.

(Just for completeness, the University of Portland used this text for a 400-level semester course on QC. It's not too bad, although it expects you to be quite fluent in number theory and linear algebra.)