Seminars Archive

Coherent Diffraction Imaging Project at FERMI@Elettra: First commissioning results and research opportunities

Abstract
The high transverse coherence and peak brightness of ultra-short SASE-FEL pulses have already demonstrated the extraordinary potential for coherent diffraction imaging (CDI) in a single shot experiment before the radiation damage of the sample is manifested [1]. The limitations imposed by the partial longitudinal coherence of SASE-FEL for getting selective chemical information using single shot resonant (R-) CDI, should be overcome by the seeded FEL sources. This opens unique opportunities for single-shot R-CDI experiments with access to elemental and/or magnetic structure of morphologically complex targets using the energy tunability and multiple (circular or linear) polarization of the fully coherent seeded FEL pulses. The ultimate lateral and temporal resolution are determined by the wavelength and pulse duration of such photon. The measurement station for CDI is now operating at the DiProI beamline of the FERMI@Elettra seeded free electron laser facility (s-FEL) [2]. The station is designed to meet the requirements for performing a wide range of static and dynamic studies and has been already commissioned using both synchrotron and FEL radiation [3]. This presentation will report the result of the commissioning and the first single shot and resonant CDI measurements obtained using the FERMI@Elettra source [4]. The energy tunability and multiple (circular or linear) polarization of the FERMI@Elettra pulses has allowed to have direct access to elemental and magnetic structure information of thin Co/Pt multilayer film, from a set of speckles, measured with wavelengths matching the M- absorption edges of Co. [1] H. N. Chapman et al, Nature Physics 2, 839 - 843 (2006). [2] E.Allarie et. al, Nature Photonics 6, 699-704 (2012) [3] E. Pedersoli et al, Rev. Sci. Instrum. 82, 043711 (2011). [4] F. Capotondi et al. in preparation.