Self-aligned fiber-based dual-beam source for STED nanolithography [Early Posting]
A fiber-based source that can be exploited in stimulated emission depletion (STED) inspired nanolithography setup is presented. Such a source maintains the excitation beam pulse, generates ring-shaped depletion beam and automatically realizes dual-beam co-axial alignment that is critical for two beam nanolithography. The mode conversion of depletion beam is realized by using customized vortex fiber, which converts the Gaussian beam into donut-shaped azimuthally polarized beam. The pulse width and repetition frequency of the excitation beam remain unchanged and its polarization states can be controlled. According to the simulated point spread functions of each beam in the focal region, the full-width at half-maximum of the effective spot size in STED nanofabrication could decrease to less than 28.6 nm.
Chen Jian,Chen Guoliang,Zhan Qiwen. Self-aligned fiber-based dual-beam source for STED nanolithography[J].Chinese Optics Letters,2021,19(7):07.