Two-photon fluorescence correlation spectroscopy through a dual-clad optical fiber

作者：Chang Yu Chung^*; Ye Jing Yong; Thomas Thommey; Chen Yi; Baker James R Jr; Norris Theodore B

来源：Optics Express, 2008, 16(17): 12640-12649.

We report on the utilization of a dual-clad optical fiber for two-photon excited fluorescence correlation spectroscopy (FCS). High excitation efficiency is obtained by sending prechirped ultrafast pulses through the single-mode core of the fiber, while the fluorescence collection efficiency is enhanced because of the larger numerical aperture of the inner cladding. We show that the utilization of a dual-clad fiber is critical for ultrasensitive two-photon fluorescence detection. Our system has the ability to detect fluorescent nanospheres as small as 12 nm in radius. Quantum dots of radius 7 nm are also measured and show excellent signal to noise ratio. The particle sizes obtained from the fiber FCS system were confirmed by measurements using a commercial dynamic light scattering (DLS) system.

• 出版日期2008-8-18
• 单位河北医科大学