Transcript Powerpoint
Ultra-Stable Lasers Supervisor Dr Randy Bartels Team Members Steven Dorlac, Andrew Wiersma, Daxsamuel Chitechi, Derrick Bernallie Ultra-Stable Lasers Project Overview • Develop an Optically-Based Clock – Ultra-Stable External Cavity Diode Laser (ECDL) • Stable Optical Frequency Comb (image shown on right) • Driving/Stabilizing Electronics – Applications • Precision Clocks • Telecommunications • Precision Navigation Source: Encyclopedia of Laser Physics and Technology (website) Ultra-Stable Lasers ECDL System Overview • Key Components – – – – External Cavity Diode Laser Thermoelectric Control (TEC) Power Supply (PSU) Piezo-Electric Power Supply (PZT PS) – Diode Driver – Loop Control/Filter – Optics Current Controller Ultra-Stable Lasers Semester Goals and Assignments • Develop ECDL electronics – Diode Driver: Andy Wiersma – TEC: Dax Chitechi – Power Supply: Derrick Benallie – Control/Filter: Steven Dorlac Current Controller • Supplies a very low noise current to the LASER diode • Typical Inputs – Power Supply • Supplies power to the Current Driver to produce a current – Servo Circuit • Provides feedback to the Current Driver to compensate for changes • Typical Outputs – Laser Diode • Supplies Current to the Diode Current Controller Current Controller Overview Current Controller Key Parts 1) Supply Source 2) Circuit Feedback 3) Current Line 4) Output to Diode Thermoelectric Controller • Maintain the ECDL at constant temperature. • Typical inputs: – Thermistor & thermocouple • Typical outputs: – Peltier cooler & heater TEC Thermoelectric controller overview Thermoelectic Controller Key Parts 1) Low power low cost 2.5V reference 2) Gain stage 3) Peltier cooling and heating stage Power Supply • Supplies Power other Circuits – General power • TEC • PZT PS • Current Controller • Cost effective to simply purchase PSU Pulsed Power Supply • Supplies Power to the PZT Driver – Provides high voltage supply to supply to PZT • Piezoelectric Disc – Mounted to back of optical mirrors – Changes Cavity Length • Changes output freqency PZT PS Pulsed Power Supply Pulsed Power Supply • More efficient • Carefully designed not to have high power peaks Control/Filter Electronics • Stabilizes ECDL Frequency • Can be cascaded • Typical Inputs – Photodetector • Typical Outputs – Piezo Disc • Adjusts External Cavity – Diode Driver • Adjusts Current to Diode Control Control/Filter Electronics Key Components Budget 1) Current Controller Parts: $138.43 2) Thermoelectric Cooling Parts: $76.15 3) Power Supply Parts: $133.77 4) Loop Electronics Parts: $109.31 -Total for parts so far:$457.67 -Amount coming in from senior design: $350 -We plan on getting the rest of our funding from Prof. Bartels for the PCB and any extra costs we come across -PCB: ~$50 for each circuit= $200 -One major expense we still have other than the PCB is two EMCO model G03 which we are currently looking for more affordable alternative replacement parts Review • ECDL Circuits – Connections – Purpose – Features Current Controller Next Semester Plans/Goals • Design, Integrate and Build ECDL components – Diode Housing, External Cavity, Mirrors, Gratings, Piezo Discs, Photodetector • Assemble ECDL system – Attach electronics – Setup and calibration of electronics • Achieve stable optical comb output from ECDL Thanks for Listening Any Questions?