SIMULTANEOUS MEASUREMENT OF TWO ARBITRARY ULTRASHORT LASER PULSES USING DOUBLE-BLIND FREQUENCY-RESOLVED OPTICAL GATING

ULTRAFAST LASERS (LASERS THAT GENERATE PULSES WITH DURATIONS OF ~10 PICOSECONDS OR LESS) HAVE A LARGE NUMBER OF APPLICATIONS IN BIOCHEMISTRY, CHEMISTRY, PHYSICS, AND ELECTRICAL ENGINEERING. UNFORTUNATELY, THESE SYSTEMS ARE DIFFICULT TO USE LARGELY BECAUSE ULTRAFAST LASER PULSES ARE EXTREMELY DIFFICULT TO CHARACTERIZE AND FEW TECHNIQUES ARE CURRENTLY AVAILABLE. THOSE THAT ARE AVAILABLE USUALLY ARE DIFFICULT TO USE, DO NOT PROVIDE IMMEDIATE FEEDBACK ABOUT SYSTEM OPERATION, AND ARE TIME CONSUMING. AN INSTRUMENT IS BEING DEVELOPED THAT WOULD COMPLETELY CHARACTERIZE (MEASURE THE INTENSITY AND PHASE) TWO ULTRASHORT LASER PULSES SIMULTANEOUSLY, ULTIMATELY IN A SINGLE SHOT, WHICH WOULD FACILITATE MEASUREMENT OF LOW ENERGY ULTRASHORT PULSES, HELP TO CHARACTERIZE ULTRASHORT LASER SYSTEMS, AND WOULD ALSO ALLOW SUB-PULSE DYNAMICS TO BE RESOLVED. THE DEVICE IS BASED ON A NEWLY INVENTED TECHNIQUE TO MEASURE THE INTENSITY AND PHASE OF ULTRASHORT LIGHT PULSES CALLED FREQUENCY-RESOLVED OPTICAL GATING (FROG). HOWEVER, RATHER THAN USE THE PULSE TO GATE ITSELF VIA THE OPTICAL KERR EFFECT, THE TECHNIQUE USES AN UNKNOWN PULSE TO GATE A DIFFERENT UNKNOWN PULSE. LIKE FROG, THE GATED PULSE IS SPECTRALLY RESOLVED FOR A SERIES OF TIME DELAYS. THE INTENSITY AND PHASE OF BOTH PULSES ARE FOUND BY USING TWO-DIMENSIONAL PHASE RETRIEVAL METHODS THAT ARE COMMONLY USED IN ASTRONOMY AND IMAGE PROCESSING TO DEBLUR IMAGES. THIS DEVICE WOULD NOT ONLY MEASURE PULSES, BUT WOULD PROVIDE INSIGHT INTO ULTRAFAST LASER OPERATION AS WELL, AND, HENCE, ALLOW THEM TO BE USED MORE EASILY AND MORE EFFECTIVELY.