EE 16 46816 568 Waveguide photonic devices Lecture

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 1. Mach-Zehnder EO modulator n a 2 a 1 A b 1 a 3 50% n 2 b 3 Aout Electro-optic effect, n 2 changes with E -field

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 2. Optical Switches High power modulators Filters • Provide high-speed data stream for shared users • Reduce noise Switches • Network configuration • Dynamic routing data traffic

EE 16. 468/16. 568 Waveguide photonic devices Types of Optical Switches 1. Micro-electro-mechanical systems (MEMS) Disadvantages: • Hard for switch array • Hard for alignment • Reliability issues From Lucent, Bell lab Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices 2. Liquid crystal based optical switch Disadvantages: • Free space based, hard to integration • Hard for alignment • Large size Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 3. Thermo-optic switch, directional coupler based Disadvantages: • Wavelength sensitive • Large size for switch array Heater P 1 Heater P 0=1 L P 2 Coupler TO switch P 2 Input waveguide output waveguides

EE 16. 468/16. 568 Waveguide photonic devices 4. Thermo-optic switch, total internal reflection based n 1 n 2 Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 Advantages of TIR based thermo-optic switch • Wavelength insensitive • Easy array operation TIR TO switch array

EE 16. 468/16. 568 Waveguide photonic devices 2 x 2 thermo-optic switch and 8 x 8 switch arrays Output Wavegui des Electrod e Pads Input 2 optical chips, each with an array of Wavegui 8 x 8 optical switches des Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Device performance Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices 5. Resonator based EO optical switch Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices 5. Resonator based EO optical switch array • Very compact size • Easy scale up to Nx. N arrayt • Low power consumption, high yield and high reliability Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Wavelength division multiplexing (WDM) technology Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Coarse Wavelength-division Multiplexing (CWDM) Dense Wavelength-division Multiplexing (DWDM) Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices 3. Array waveguide grating (AWG) Lecture 3

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 3. Array waveguide grating (AWG) Nc: index in channel L 0 +(m-1) L ns L 0 Center channel

EE 16. 468/16. 568 Waveguide photonic devices Lecture 3 3. Array waveguide grating (AWG) L 0 +(m-1) L Foca l leng th f d D L 0 Upper one channel: Channel m d D L – (D/f)d L 0 +(m-1) L – (D/f)(m-1)d Wavelength ’ goes the next channel