title: Two-photon two-focus fluorescence correlation spectroscopy with a tunable distance between the excitation volumes.
mesh_terms: D004058:Diffusion; D007368:Interferometry; D007834:Lasers; D008853:Microscopy; D008956:Models, Chemical; D017785:Photons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*