Compact and low driving power silica-based 1/spl times/N planar lightwave circuit switches with super high delta waveguides and heat insulating grooves

We have successfully realized compact 4-arrayed 1/spl times/8 and 1/spl times/128 PLC-SWs with a low driving power by using SH/spl Delta/ waveguides and heat insulating grooves. A 4-arrayed 1/spl times/8SW had good optical characteristics, namely a loss of 2.0 dB and crosstalk of -50 dB, despite its compact and low power configuration. A 1/spl times/128SW also had good optical characteristics and low driving power, and was very compact, that is 1/3 the size of a previously developed SH/spl Delta/ 1/spl times/128SW. Since these PLC-SWs are practical for use as compact and simple switch modules, they are applicable to large-scale optical switch systems such as optical cross connect and optical add-drop multiplexing systems.