title: Two-dimensional higher order noise spectroscopy up to radio frequencies.
abstract: Going beyond the usual determination of the frequency-resolved power spectrum of an electrical noise signal, we implement a setup for the determination of a frequency-resolved two-dimensional correlation spectrum. We demonstrate measurements of two-dimensional correlation spectra with sampling rates up to 180 MSamples/s and real-time numerical evaluation with up to 100% data coverage. As an example, the purely Gaussian behavior of 1/f resistor noise is demonstrated with unprecedented sensitivity by verifying the absence of correlations between different frequencies. Unlike the usual power spectrum, the correlation spectrum is shown to contain information on both the homogeneous and inhomogeneous linewidths of a signal, suggesting applications in spin noise spectroscopy and signal analysis in general.
authors.affiliation: Arbeitsgruppe Spektroskopie der kondensierten Materie, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Starosielec
authors.forename: Rachel
authors.initials: R
authors.lastname: Fainblat
authors.forename: Jörg
authors.initials: J
authors.lastname: Rudolph
authors.forename: Daniel
authors.initials: D
authors.lastname: Hägele