Direct Laser Writing of Refractive Index Micro-Structures in Lithium Niobate
We report on micro-structuring of iron-doped lithium niobate using femtosecond direct laser writing (DLW) technique. Formation of extended, stable index modulation micro-structures, such as diffraction gratings and linear waveguides is achieved by translation of a focused femtosecond laser beam inside lithium niobate crystals. From diffraction efficiency of the recorded gratings refractive index modulation amplitude of n ~ 10-3 is estimated. It is demonstrated that the recorded structures can be optically erased and re-written.
V. Mizeikis et al., "Direct Laser Writing of Refractive Index Micro-Structures in Lithium Niobate", Advanced Materials Research, Vol. 222, pp. 118-121, 2011