Ion Trap Quantum Computer Architecture
With the deadline for the 2006 conference in a week, it seems like a good time to talk about the International Symposium on Computer Architecture. ISCA is the premiere forum for architecture research; it's very competitive and papers there are, as a rule, highly cited.
Mark Oskin's group published a good ion trap system architecture paper in ISCA 2005. The paper "An Evaluation Framework and Instruction Set Architecture for Ion-Trap based Quantum Micro-architectures" shows how to take the technology designed by the Wineland group at NIST and begin designing a complete computer out of it. They evaluate different choices of layout: how many traps per segment of wire, how to minimize the number of turns an ion must make, etc. They also discuss their tool chain for doing much of the work.
When we systems folk (there are only a handful of us in quantum computing, with Mark leading the class) talk about architecture, this is the kind of thing we mean. This work suggests that most of the decoherence in an ion trap system will come from turning corners, and therefore the research they are doing has the potential to have a dramatic effect on the practical threshold necessary for QEC to be effective.
[Disclaimer: Mark and I have a joint paper under consideration, though I had nothing to do with the work described here.]