Self-switching microresonator optical switch

An optical switch comprising:

• a microresonator comprising a silicon-rich silicon oxide layer and a plurality of silicon nanoparticles within the silicon-rich silicon oxide layer, the microresonator configured to receive signal light having a signal wavelength and an optical power, wherein at least a portion of the microresonator is responsive to the signal light by undergoing a refractive index change at the signal wavelength, the refractive index change dependent on the optical power of the signal light;
• and
• an optical coupler optically coupled to the microresonator and configured to be optically coupled to a signal source, wherein the optical coupler transmits the signal light from the signal source to the microresonator,
• wherein transmission of the signal light through the optical switch is dependent on a relationship between the optical power of the signal light and a predetermined threshold level.