Photon correlation spectroscopy of polymer solutions: Improved subdistribution method

Photon Correlation Spectroscopy

Two-photon standing-wave fluorescence correlation spectroscopy.

A fluorescence correlation spectroscopy experiment that combines two-photon excitation and a standing-wave interference pattern is presented. The experimental correlation function can be analyzed using a simple expression involving (1) an exponential decay with time constant tau(f), which reflects diffusion across the interference fringes, and (2) a longer-lived decay with time constant tau(ome...

Low-coherence heterodyne photon correlation spectroscopy.

Photon correlation spectroscopy (PCS) is routinely used to investigate the dynamics of colloidal particles undergoing Brownian motion. This technique is applicable to low-density colloidal suspensions in which the effects of multiple light scattering are minimal. We introduce a new low-coherence heterodyne PCS technique that allows direct investigation of colloidal suspensions of higher concent...

Measurement of the velocity difference by photon correlation spectroscopy: an improved scheme.

Homodyne photon correlation spectroscopy is used to measure the velocity difference delta v (l) over varying distance l. Different length scales are probed when the magnification factor M and the width S of a slit in the collecting optics are varied. The measured intensity autocorrelation function is found to be of scaling form for different values of M, provided S is kept at a value below the ...

Fluorescence correlation spectroscopy in polymer science

Fluorescence correlation spectroscopy (FCS) is a well-established technique for studying dynamic processes and interactions with minimal invasion into the corresponding system. Even though FCS has been mainly applied to biological systems, within the last 15 years an increasing number of studies in material sciences have appeared, demonstrating its enormous potential also for this field. Apart ...