danielsank / phd-thesis Goto Github PK

ideally something like this or like this.

Line 113 of Introduction/introduction-content.tex:

A famous algorithm for factoring prime numbers, Shor's algorithm

Prime numbers don't need to be factored.

The thesis used to sit in my theory repo, so the import paths expected various files to be in various places. Now the repos are separate, so I either have to use git submodules or use symlinks.

Use inkscape command line mode.

I think there was an "important insight" that I didn't really capture until I was doing some in-depth calculations: the filter enhances κr by ~ QF compared to the same resonator/coupler without the filter. Now that I get it, it seems obvious, but to be honest, it didn't leap out at me for a long time. It's clear in your thesis equation (4.10), but perhaps this deserves a sentence emphasizing it.

The emphasis is on improving κr*T1, but if I haven't realized that κr and T1 both increase when you use the filter (and primarily κr increases!), a plot of T1 that includes filter vs. no filter is somewhat confusing. There's not much change to T1 vs. the factor of ~ 80 improvement in κr*T1 I'm looking for. I attached a plot of T1 and κr*T1 versus qubit frequency. The two lines have the same resonator/coupler, but one is just hanging on a transmission line, while the other is in a filter based on Kelly 2015. This is from the same calculation I was emailing you about.

Usually when I hear people talking about this filter, it's framed as "decreasing Purcell rate while keeping the same measurement time" (where measurement time is of order 10/κr). Of course, you can use the filter for that, but it seems like one of the big benefits is getting 1/κr down near 10 ns, which is difficult with a simple hanger measurement. That's all while keeping the Purcell rate reasonable. If I understand correctly, that's its main function going from Barends 2014 to Kelly 2015.

Compare with derivations preceding D.54. This looks like a typo.