1550 nm 1 Antimony compounds 1 Calculation models 1 Finite difference time domain method 1 Ge2Sb2Te5 1 Germanium compounds 1 Low-loss 1 Material layers Optical switches 1 Optical triode 1 Optical waveguides 1 Optical- 1 Parallel waveguides 1 Phase change materials 1 Selenium compounds 1 Signal light 1 Silicon photonics 1 Switch phasis 1 Tellurium compounds 1 optical switch 1 optical triode 1 optical waveguide 1 phase-change material 1 silicon photonics 1