Patent ID: 8610994
Filing Date: 2013-12-17
Classification: G02F,H01Q

Abstract:
1. An optical device comprising: a microresonator; and a waveguide situated adjacent the microresonator so as to define a coupling region within which there is optical coupling between the microresonator and the waveguide across a gap of width W along a coupling length L that is quantifiable, for an operating range of wavelengths, by a coupling coefficient κ; wherein: the waveguide is adapted for receiving an input optical signal, L and W are selected to give a value to κ such that the waveguide is overcoupled to the microresonator, the microresonator is adapted for receiving the input optical signal via the waveguide and phase-shifting the input optical signal, by a controllable phase shift that is responsive to a phase-tuning condition, to form an output optical signal, the output optical signal being coupled into the waveguide via the microresonator and transmitted by the waveguide, and L and W are further selected such that the value of κ maximizes the sensitivity of the controllable phase shift to the phase-tuning condition subject to a specified limit on how much the output optical signal is attenuated relative to the input optical signal.