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We demonstrate a single-shot digitizer with a 10 Tsample/ s sampling rate. This feat is accomplished with a photonic time stretch preprocessor that slows down the electrical waveform by an unprecedented factor of 250 before it is captured by a commercial electronic digitizer. To achieve such a large stretch factor, distributed Raman optical amplification is realized inside the dispersive element that performs the time stretch.

Dispersive Fourier transformation is a powerful technique in which spectral information is mapped into the time domain using chromatic dispersion. It replaces a spectrometer with an electronic digitizer, and enables real-time spectroscopy. The fundamental problem in this technique is the trade-off between the detection sensitivity and spectral resolution, a limitation set by the digitizer's bandwidth. This predicament is caused by the power loss associated with optical dispersion. We overcome this limitation using Raman amplified spectrum-to-time transformation. An extraordinary loss-less -11.76 ns/nm dispersive device is used to demonstrate single-shot gas absorption spectroscopy with

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The ability to control chromatic dispersion is paramount in applications where the optical pulsewidth is critical, such as chirped pulse amplification and fiber optic communications. Typically, devices used to generate large amounts (>100 ps/nm) of chromatic dispersion are based on diffraction gratings, chirped fiber Bragg gratings, or dispersion compensating fiber. Unfortunately, these dispersive elements suffer from one or more of the following restrictions: (i) limited operational bandwidth, (ii) limited total dispersion, (iii) low peak power handling, or (iv) large spatial footprint. Here, we introduce a new type of tunable dispersive device, which overcomes these limitations by leveraging the large modal dispersion of a multimode waveguide in combination with the angular dispersion of diffraction gratings to create chromatic dispersion. We characterize the device's dispersion, and demonstrate its ability to stretch a sub-picosecond optical pulse to nearly 2 nanoseconds in 20 meters of multimode optical fiber. Using this device, we also demonstrate single-shot, time-wavelength atomic absorption spectroscopy at a repetition rate of 90.8 MHz.

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