The invention discloses a method for simultaneously achieving
laser frequency doubling and line aggregation in an optical
superlattice. The method comprises the following steps that 1, an upper inclined domain structure and a lower inclined domain structure with the same period are designed in the
superlattice, and are distributed symmetric about the
crystal light passing direction; 2, when fundamental
waves are vertically shot into the
superlattice in an incident mode, the upper half portion of the superlattice can generate
laser frequency doubling
waves bent downwards, the
lower half portion of the superlattice can generate
laser frequency doubling
waves bent upwards, the
laser frequency doubling waves generated by the upper half portion and the
laser frequency doubling waves generated by the
lower half portion are the same in bending angle and strength, and accordingly, a line focusing interference pattern similar to an
axicon can be generated on the overlapped area of the upper half portion and the
lower half portion; 3, after lasers enter the superlattice,
reciprocal lattice vectors provided by the domain structures of the superlattice can compensate for
wave vector mismatching between fundamental waves and the
laser frequency doubling waves, and a triangle with matched wave vectors is formed. Frequency doubling of lasers and line aggregation are achieved simultaneously through the periodically-symmetric and inclined domain structures in the optical superlattice.