Abstract: This invention provides ultra-low noise lasers with exceptional performance through the use of ultra-low loss microresonator based filters/reflectors including multiple (?3) microresonator rings with different ring radii. The ultra-low loss microresonators provide a long effective laser cavity length enabling very narrow linewidth laser operation, with multiple (?3) microresonators providing extremely high selectivity of the lasing mode over a very wide wavelength range; supporting single wavelength and widely tunable wavelength laser operation. The highly selective and also low loss filter/reflector supports high output power operation of the lasers.

Abstract: The invention provides a new linearized electro-optic modulator in which linearization is achieved by modulating the index of a Bragg grating reflector placed in the arm(s) of a Michelson Interferometer. This grating-assisted Michelson Interferometer (GAMI) modulator operates as either an intensity or amplitude modulator, and is shown to significantly improve the linearity of microwave photonics links. Furthermore, this modulator improves the performance of optical communication systems using advanced modulation formats.

Abstract: This invention provides an optical device comprising a large group of non-uniform resonators operating cumulatively as a ‘super-ring’ to provide a controllable group delay with large bandwidth. The super-ring tuning is performed by a single control. The device may include two super-rings, each includes a large number of resonators with a resonant frequencies centered around ?1 and ?2 respectively. The invention provides multiple ways to improve the delay duration, bandwidth and the tuning speed, and overcomes the issue of non-uniformity of resonance frequency for devices incorporating multiple optical resonators.

Abstract: This invention provides a balanced thermal approach to the tuning of an optical time delay device in order to eliminate any long-term time response of the device performance due to thermal time constants of the device, its mount, packaging or electronic temperature control circuits. The invention provides multiple ways to improve the thermal tuning speed of the balanced thermal approach. Additionally, the invention overcomes an issue of microresonator non-uniformity by operating a large group of microresonators as a ‘super-ring’ by tuning the large group together to provide a controllable group delay with large bandwidth.

Abstract: This invention provides a tunable delay of an optical signal having multiple frequency components. The delay comprises at least a first and a second integrated resonators coupled sequentially to a waveguide; the resonators have angular resonant frequencies ?1=?0??? and ?2=?0+?? respectively, ?0 is a median frequency of an input optical signal and ?? is a tunable deviation from the median frequency. The device is providing a nearly equal true time delay to all frequency components in the output signal.

Abstract: This invention provides a tunable delay of an optical signal having a carrier with an angular frequency ?0 and a single side band having a signal band with a median angular frequency ?r. The delay line comprises at least a first, a second and a third integrated resonators coupled sequentially to a waveguide. The first and the second resonators have angular resonant frequencies ?1=?r??? and ?2=?r+?? respectively, where ?? is a deviation from the median frequency. The third resonator provides a phase delay difference between the phase at the optical carrier ?0 and the phase at the median frequency ?r equal to (?r??0)Td, where Td is the time delay. The device provides an equal group delay to all frequency components in the output signal and also equal phase delay for all frequency components of an RF signal when the optical signal is downconverted at a photodetector. The device may find applications controlling the time delay to antenna elements in a phased array system.