Tantalum pentoxide (Ta₂O₅) based athermal micro-ring resonator

422 Million intrinsic quality factor planar integrated all-waveguide resonator with sub-MHz linewidth

“…Frequency stabilization can be determined by the resonator's close-to-carrier frequency noise, jitter, and long-term drift. Stabilization of the lowfrequency noise components (e.g., 1 Hz and less) will require cavity designs that also have near-zero thermal expansion coefficients [66][67][68] and dampened responses to the environmental disturbances 69 determined in large part by packaging and mounting as well as the resonator material and design. These aspects of resonator stabilization are the subject of ongoing research for waveguide resonators.…”

3D design and analysis of an electro-optically tunable athermal and polarization-insensitive ring resonator-based add-drop filter for DWDM systems

“…Replacing silicon with silicon-rich nitride ( ) with a low index contrast, simultaneously reduces the difference in the coupling efficiencies for both polarizations. Titanium oxide was chosen for its negative TOC and its insensitivity to humidity as compared to polymers [33] . The material system is simultaneously athermal, polarization-insensitive, CMOS-compatible, and electro-optically tunable.…”

“…Scientists are still extensively researching ring resonator-based optical filters and are trying to improve the performance in one or more of the following performance criteria with regard to the application: insertion losses [24] , bending losses [25] , size [26] , channel spacing [27] , free spectral range (FSR) [28] , full wave half maximum (FWHM), quality (Q) factor, extinction ratio [29] , cross-talk, tuning range, tuning speed [30] , thermal dependence and polarization sensitivity [31] [32] [33] . Solutions have been proposed to reduce polarization sensitivity and thermal instability [7] [31] [34] .…”

“…Solutions have been proposed to reduce polarization sensitivity and thermal instability [7] [31] [34] . In fact, a tantalum pentoxide ( )-based athermal micro-ring resonator has been designed with a propagation loss of 0.56 dB/cm, a Q factor of 5000 and a large radius of 50 μm [33] . Microring resonators (MRRs) in linear materials such as silicon-lithium niobate [30] and nonlinear materials, such as silicon-graphene [35] [4] show a great potential for providing tunable filters without addressing the temperature and polarization dependence behavior.…”

Design and Analysis of Ultralow Voltage Graphene on the Silicon Rich Nitride Tunable Ring Resonator-Based Add-Drop Filter for DWDM Systems

“…To address the thermal dependence, athermal core materials such as Ta 2 O 5 materials [24] or top cladding materials with negative thermo-optic coefcients such as titanium dioxide [25,26], sol-gel materials [27], chalcogenides [14], and polymethyl-methacrylate (PMMA) [28] have previously been used to ofset the positive coefcient of the core and substrate materials (Table 1).…”