Fig. 1
Comparison between conventional XMCD experiment and the adaptively designed XMCD experiment. (left) Flowchart for conventional XMCD spectroscopy experiment. First, data points are sampled to obtain a spectrum for opposite directions of X-ray polarisations or magnetisation directions at each energy point. Next, magnetic moments are evaluated from the experimental spectra. (right) Flowchart for the adaptive design of the XMCD spectroscopy experiment. First, initial data points are sampled to obtain an experimental spectrum as the training data set for opposite directions of X-ray polarisations or magnetisation directions at each energy point. Next, the Gaussian process (GP) model predicts the spectra, and magnetic moments are evaluated from the predicted spectra. The convergence of values of the magnetic moments are checked in order to determine whether to sample new data points and return to predicting spectra or stop the experiment. We examined two and three options for sampling initial data points and selecting new sampling point, respectively
