We demonstrate a silver nanowire ring resonator with a ring diameter of 10.2μm.The ring cavity is formed by coupling both ends of a 145-nm-diameter single silver nanowire into a closed loop.A Q-factor of 160 and a free spectral range of 10.6 nm are obtained for light centered around 800 nm.The self-coupled ring structure offers opportunities for realizing compact plasmonic resonators with tight confinement for hybrid optical and plasmonic signal processing.
We investigate femtosecond laser direct writing （FLDW） in the fabrication of magneto-optical （MO） microstructures. The experimental results show that FDLW can introduce positive refractive index change in the MO materials. With the increase of the writing intensity of femtosecond laser pulses, refractive index change increases, whereas Verdet constant of the damaged area decreases nonlinearly. With suitable writing intensity, we obtain a single-mode waveguide in which Verdet constant is 80% of the bulk MO glass.
Aring-shaped all fiber tunable Yb-doped fiber laser with tuning range over 20 nm is demonstrated by using a fiber Mach-Zenhder interferometer as an intra-cavity filter which is constructed with two 3-dB optical couplers.The method for fabricating the fiber Mach-Zenhder interferometer is detailed.The fiber laser has a moderate milli-Watt level output power over the whole tuning range from 1050 to 1071 nm,a side-band suppression ratio greater than 45 dB,and a bandwidth less than 0.1 nm.
