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Chrono CDI: Coherent diffractive imaging of time-evolving samples

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 نشر من قبل Andrew Ulvestad
 تاريخ النشر 2016
  مجال البحث فيزياء
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Bragg coherent x-ray diffractive imaging is a powerful technique for investigating dynamic nanoscale processes in nanoparticles immersed in reactive, realistic environments. Its temporal resolution is limited, however, by the oversampling requirements of 3D phase retrieval. Here we show that incorporating the entire measurement time series, which is typically a continuous physical process, into phase retrieval allows the oversampling requirement at each time step to be reduced leading to a subsequent improvement in the temporal resolution by a factor of 2 to 20 times. The increased time resolution will allow imaging of faster dynamics and of radiation dose sensitive samples. This approach, which we call chrono CDI, may find use in improving time resolution in other imaging techniques.

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