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Coherent Diffraction Imaging Coherent Diffraction Imaging Ian Robinson London Centre for Nanotechnology Felisa Berenguer Diamond Light Source Ross Harder Richard Bean Structural Biology Moyu Watari Oxford University March 2009 I. K. Robinson, STRUBI Mar 2009 1 Outline • Imaging with X-rays • Coherence based imaging • Nanocrystal structures • Extension to phase objects • Exploration of crystal strain • Biological imaging by CXD I. K. Robinson, STRUBI Mar 2009 2 Types of Full-Field Microscopy (Y. Chu) X-ray Topography Projection Imaging, Tomography, PCI Miao et al (1999) Coherent X-ray Diffraction Coherent Diffraction imaging Transmission Full-Field MicroscopyI. K. Robinson, STRUBI Mar 2009 3 Full-Field Diffraction Microscopy Lensless X-ray “Microscope” APS ξHOR= 20µm, focus to 1µm NSLS-II ξHOR= 500µm, focus to 0.05µm I. K. Robinson, STRUBI Mar 2009 4 Longitudinal Coherence Als-Nielsen and McMorrow (2001) I. K. Robinson, STRUBI Mar 2009 5 Lateral (Transverse) Coherence Als-Nielsen and McMorrow (2001) I. K. Robinson, STRUBI Mar 2009 6 Smallest Beam using Slits (9keV) 10 Beam 100mm away size (micron) 50mm away 20mm away 10mm away 0 0 10 Slit size (micron) I. K. Robinson, STRUBI Mar 2009 7 Fresnel Diffraction when d2~λD X-ray beam defined by RB slits Visible Fresnel diffraction from Hecht “Optics” I. K. Robinson, STRUBI Mar 2009 8 Diffuse Scattering acquires fine structure with a Coherent Beam I. K. Robinson, STRUBI Mar 2009 9 Coherent Diffraction from Crystals k Fourier Transform h I. K. Robinson, STRUBI Mar 2009 10 I. K. Robinson, STRUBI Mar 2009 11 Chemical Synthesis of Nanocrystals • Reactants introduced rapidly • High temperature solvent • Surfactant/organic capping agent • Square superlattice (200nm scale) C. B. Murray, IBM J. Res. & Dev. 45 47 (2001) I. K. Robinson, STRUBI Mar 2009 12 Chemically Synthesized Silver Nanocubes Yugang Sun and Younan Xia, Science 298 2177 (2003) I. K. Robinson, STRUBI Mar 2009 13 Rocking scan of Ag cubes with 0.01° steps I. K. Robinson, STRUBI Mar 2009 14 I. K. Robinson, STRUBI Mar 2009 15 Generic “Error Reduction” method J. R. Fienup Appl. Opt. 21 2758 (1982) R. W. Gerchberg and W. O. Saxton Optik 35 237 (1972) I. K. Robinson, STRUBI Mar 2009 16 3D Ag Nano Cube Yugang Sun and Younan Xia, Science 298 2177 (2003) I. K. Robinson, STRUBI Mar 2009 Isosurface of 3D Phase Bump I. K. Robinson, STRUBI Mar 2009 18 3D phase map sections I. K. Robinson, STRUBI Mar 2009 19 Sensitivity to strain Δφ = kf·u–ki·u = Q·u I. K. Robinson, STRUBI Mar 2009 20 I. K. Robinson, STRUBI Mar 2009 21 Nanocantilevers Dr Rachel McKendrie I. K. Robinson, STRUBI Mar 2009 22 Strain induced by thiol binding Moyu Watari, UCL, Oct 2008 I. K. Robinson, STRUBI Mar 2009 23 CXD applied to collagen Felisa Berenguer, LCN • Collagen is the most common protein in animal tissue (bones, teeth, tendon, cartilage, connective tissue) • Potential applications in medicine (artificial bone, skin diseases) • Collagen packing to built-up fibres is not completely understood Different proposed models by Orgel 2007, Wess 2006, Bozec 2007 … SEM [Cisneros, 2006] [Hodge and Petruska, 1976] I. K. Robinson, STRUBI Mar 2009 24 AFM imaging of rat-tail collagen Dehydrated rat tail tendon tissue Strong D-banding with 67 nm periodicity: Diffraction pattern with strong meridional maxima at multiples of 1/67 nm-1 I. K. Robinson, STRUBI Mar 2009 25 First experimental results on collagen Rat tail tendon tissue 0 order First meridional reflection at α1/67 nm-1 I. K. Robinson, STRUBI Mar 2009 26 X-ray Ptychography 10 µm beam First meridional reflection Dark field imaging: collagen distribution in different tissues I. K. Robinson, STRUBI Mar 2009 27 X-ray Ptychography J. M. Rodenburg et al, Phys. Rev. Lett. 98 034801 (2007) I. K. Robinson, STRUBI Mar 2009 28 X-ray Ptychography P. Thibault et al, Science 321 379 (2008) I. K. Robinson, STRUBI Mar 2009 29 Reconstruction of Probe P. Thibault et al, Science 321 379 (2008) I. K. Robinson, STRUBI Mar 2009 30 Niobium (110) Thin Film Grains Richard Bean, I-16, Nb110-35 Jan 2009 I. K. Robinson, STRUBI Mar 2009 31 Ptychography phasing tests Diffraction patterns computed from i) simulated domain array ii) propagated pinhole function with an overlap of ~80% between adjacent positions. Richard Bean, UCL, Jan 2009 I. K. Robinson, STRUBI Mar 2009 32 Ptychography phasing tests Sheffield Ptychography algorithm starting with an array of random numbers in both amplitude and phase. 7x3 array. Richard Bean, Jan 2009 Amplitude and phase after 1 iteration. Amplitude and phase after 20 iterations. I. K. Robinson, STRUBI Mar 2009 33 Improved collagen sample prep Diamond I-22, Nov 2008 I. K. Robinson, STRUBI Mar 2009 34 Evolution of Collagen Speckles probe position I. K. Robinson, STRUBI Mar 2009 35 ‘Random’ phase plate analyser Joan Vila (PSI), Fucai Zhang (Sheffield) Pinhole Sample Analyser 1µm I. K. Robinson, STRUBI Mar 2009 36 Phase plate scan near forward direction 1µm step per frame I. K. Robinson, STRUBI Mar 2009 37 Collagen, buffer and empty cell phplateFZP-236, -246 and -249 I. K. Robinson, STRUBI Mar 2009 38 Conclusions • X-ray allow 3D imaging on the nanoscale • Internal structure of Ag and Pb Nanocrystals • Phasing by computation instead of lens • Strain fields imaged from asymmetric patterns • Contact Forces and Surface Strain • Nanowire domain structures in InP, GaAs • Biological tissue accessible by ptychography I. K. Robinson, STRUBI Mar 2009 39 .
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