stevenmanton / msfn

Matlab programs to calculate mean square flux noise (MSFN) of superconducting SQUID or qubit loop.

Mean square flux noise

This repository contains the programs needed to calculate mean square flux noise (MSFN) of superconducting SQUID or qubit loops. Binaries of freely available 64-bit superconducting version of FastHenry and InductEx are included. My Matlab code implements the class iewasher, which defines properties and methods relevant for a single loop. The program batchIEW creates an array of iewasher object, where we vary a specific geometric parameter, and runBatchIEW controls the execution of the computation. The program plotIEWarray nicely plots the results.

I'm just about finished a draft describing the computation, and I'll post it as soon as it's submitted.

Steven M. Anton
Department of Physics
UC Berkeley

msfn's Issues

indefinite integral in KfromCalc.m mathematical issues

Hi there, I am currently using your code as a means to make a magnetic field calculator under C J Fourie, I noticed that the Indefinite integral function "indefInt" under the KfromCube.m file gives NaN under certain conditions, This would be because of the division by zero found in the method currently used, Would it be safe to simply make the parts that cause problems give zero as an answer when these conditions are met?

Output when used:
x =

-123.5500

y =

0.0500

z =

-0.0500

a =

0.4000

b =

0.0500

c =

0.0500

K =

1.0e-06 *

-0.5241 -Inf Inf

Unit testing

Currently, there are no unit tests written for this project to make sure it's working correctly. In particular, there should be tests to make sure that the numerical output is equivalent to the analytic solution as all the parameters are varied (position where the field is evaluated, size of the current block, direction/magnitude of current, etc.) Adding such tests would really enhance the credibility of the code and allow changes to be verified quickly.