Simplified interferometric method for the characterization of ultrashort optical pulses

Lead Research Organisation: University of Oxford
Department Name: Oxford Physics

Abstract

We propose to develop a prototype instrument for measuring the electric field of ultrafast optical pulses. This technology has applications in telecommunications, biological imaging, molecular mass spectrometry and TeraHertz radiation sensing as well as in many branches of scientific research. The instrument uses both a novel means for coding phase information about the pulse into a signal that can be measured with detectors of much slower response time than the pulses whose duration is sought (typically in the femtosecond (10.15 sec) regime), and a new method for processing the data to extract the pulse shape. The instrument will have enhanced capabilities compared to those currently on the market in terms of the amount of information provided, size, sensitivity, operating parameter range, rapidity of update and robustness to noise.Duration of Project (months)
 
Title Electromagnetic radiation pulse measurement apparatus and method 
Description  
IP Reference GB0510338.7 
Protection Patent application published
Year Protection Granted
Licensed No
 
Title Ultra-Short Optical Pulse Measurement Using a Thick Nonlinear Crystal 
Description The invention provides a pulse measurement apparatus and corresponding method. The apparatus comprises: a splitter for splitting a pulse to be measured into two sub-pulses propagating along different beam paths; a non-linear medium, capable of up-conversion of radiation propagating therethrough, arranged in said beam paths; at least one element for interfering the up-converted pulses resulting from propagation of the two sub-pulses in the non-linear medium; and detection apparatus for detecting the result of the interference to obtain at least one of spectral and temporal characteristics of the pulse to be measured. In the non-linear medium, each sub-pulse can be resolved into an o-wave component and an e-wave component propagating through the medium at a predetermined angle, and the phase-matching function for up-conversion by interaction of the o-wave component with the e-wave component in the non-linear medium is selected such that up-conversion is substantially independent of frequency for one of the o-wave or e-wave over a predetermined frequency range, and is frequency selective for the other of the o-wave and e-wave. This phase-matching function produces spectrally-sheared up-converted replicas of the pulse to be measured. 
IP Reference US2008212103 
Protection Patent granted
Year Protection Granted 2008
Licensed Yes
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