Total reflection mirrors fabricated on silica waveguides with focused ion beam

Efficient total reflection mirrors are fabricated on silica-based waveguides by direct milling with a focused ion beam. To reduce the excess losses of the mirrors, a two-step milling technique is employed that reduces the roughness of the mirror surface while maintaining a high milling rate. A focused ion beam is used to fabricate low-loss mirrors with small excess losses of about 1.0 dB.