John Sweetser

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We show that frequency-resolved optical gating combined with spectral interferometry yields an extremely sensitive and general method for temporal characterization of nearly arbitrarily weak ultrashort pulses even when the reference pulses is not transform limited. We experimentally demonstrate measurement of the full time-dependent intensity and phase of a(More)
Four-quadrature spectral interferometry using balanced coherent detection enables single-shot full-field characterization of complex-shaped optical waveforms with near quantum-limited sensitivity. A 90° optical hybrid places a waveform in four-quadrature-phases with a stronger, well-characterized reference pulse. Measurement of the four spectra with an(More)
We describe a system designed for simple and intuitive interaction with a large screen from a distance. The approach is based on an optical pointing and tracking system which has the important property that the tracking is absolute in nature. This provides several advantages over traditional methods used for input devices and remote controls, especially(More)
We demonstrate a simple, essentially alignment-free Transient-Grating Frequency-Resolved-Optical-Gating arrangement using a simple input mask that separates the input beam into three beams and a Fresnel biprism that crosses and delays them. It naturally operates single shot and has no moving parts. It is also extremely broadband and hence should be ideal(More)
Ultrashort-laser-pulse retrieval in frequency-resolved optical gating has previously required an iterative algorithm. Here, however, we show that a computational neural network can directly and rapidly recover the intensity and phase of a pulse.
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