Photonic nano-jet generated by suspended core fiber

The photonic nano-jet (PNJ) generated by the suspended core fiber (SCF) is proposed and experimentally demonstrated. Gaussian light irradiates the suspended core fiber, the PNJ is formed at the shadow-side surface of the suspended core. The measured results show that the full-width half-maximum (FWHM) of the PNJ is smaller than the incident light wavelength, and the propagation distance is several times that of the light wavelength. The experimental results are in a good agreement with the theoretical calculations. As the incident wavelength or the fiber core diameter decreases, the FWHM and decay length of the PNJ are significantly reduced. The FWHM of 0.73 lambda is achieved. The calculation results show that the SCF-based PNJ can achieve non-contact capture of a single nanoparticle. Suspended core fiber is easy to fabricate, simple and convenient to operate experimentally, and can produce a more stable PNJ that is less contaminated. Fiber-based PNJs offer new applications in particle capture and biophotonic sensing.