  We present an open-source program free to download for academic use with full
user-friendly graphical interface for performing flexible and robust background
subtraction and dipole fitting on magnetization data. For magnetic samples with
small moment sizes or sample environments with large or asymmetric magnetic
backgrounds, it can become necessary to separate background and sample
contributions to each measured raw voltage measurement before fitting the
dipole signal to extract magnetic moments. Originally designed for use with
pressure cells on a Quantum Design MPMS3 SQUID magnetometer, SquidLab is a
modular object-oriented platform implemented in Matlab with a range of
importers for different widely-available magnetometer systems (including MPMS,
MPMS-XL, MPMS-IQuantum, MPMS3 and S700X models), and has been tested with a
broad variety of background and signal types. The software allows background
subtraction of baseline signals, signal preprocessing, and performing fits to
dipole data using Levenberg-Marquadt non-linear least squares, or a singular
value decomposition linear algebra algorithm which excels at picking out noisy
or weak dipole signals. A plugin system allows users to easily extend the
built-in functionality with their own importers, processes or fitting
algorithms. SquidLab can be downloaded, under Academic License, from the
University of Warwick depository (wrap.warwick.ac.uk/129665).
