Re: Quantum Computer Hardware

Michael Nielsen (
Thu, 16 Apr 1998 18:00:54 -0600 (MDT)

On Thu, 16 Apr 1998, Dan Clemmensen wrote:

> Quantum Electronics is an exciting field with tremendous promise, but what
> this article really shows is the quantum electronics is still in its early
> lab phase. It's not really useful even for scientific instrumentation,
> and is certiainly not yet reduced to engineering practice. a lot of
> research and development is needed before we will get the first
> practical quantum computer, even using lithograghic techniques.

This is a confusion of terms. Quantum electronics is not the same as
quantum computing. Quantum electronics is simply electronics at a scale
where quantum effects become important. It is not necessary to create a
superposition of computational basis states in order to have a
functioning quantum electronic device. Such superpositions are, however,
essential to the functioning of a quantum computer (and they were
certainly created in this implementation of Grover's algorithm), and they
are what makes quantum computing a lot more difficult to achieve than
quantum electronics.

Michael Nielsen

"I know the answer! The answer lies within the heart of all mankind!
The answer is twelve? I think I'm in the wrong building."
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