Coherent X-ray Diffraction Workshop, BNL, May Keith A. Nugent ARC Centre of Excellence for Coherent X-ray Science & School of Physics The University of Melbourne Australia Opportunities for imaging with coherence
Coherent X-ray Diffraction Workshop, BNL, May Outline of Talk What can we aim for in 2013? Introduction to CDI – brief Fresnel CDI (FCDI) –Quantitative phase measurement –Application to malaria-infected red blood cell Keyhole FCDI – imaging extended objects –Application to technology problem –Early 3D results Conclusions
Coherent X-ray Diffraction Workshop, BNL, May Approaches to Coherent Imaging Holography –Recent work at BESSY –Limited path to high resolution Phase-contrast –Very extensively used –Low resolution Ptychography –SLS – Oliver Bunk –Extended objects, high resolution? CDI –Plane wave incident Isolated objects –Curved incident wave To Image extended objects in three-dimensions with 5nm resolution
Coherent X-ray Diffraction Workshop, BNL, May Coherent imaging methods are being developed. z Coherent Field Impose Measure Intensity, Keep Phase Impose “support” Guess Phase
Coherent X-ray Diffraction Workshop, BNL, May
Use prior knowledge of the incident wave to recover the “exit surface wave” leaving the object
Coherent X-ray Diffraction Workshop, BNL, May The World’s Easiest CDI Experiment FourierFresnel Fresnel Fourier
Coherent X-ray Diffraction Workshop, BNL, May Reconstruction of the Illuminating Field HM Quiney, AG Peele, Z Cai, D Paterson, KA Nugent, Nature Physics, 2, (2006)
Coherent X-ray Diffraction Workshop, BNL, May X-Ray CDI
Coherent X-ray Diffraction Workshop, BNL, May Fresnel diffraction imaging GJ Williams, HM Quiney, BB Dahl, CQ Tran, KA Nugent, AG Peele, D Paterson, M de Jonge, Physical Review Letters, 97, (2006 )
Coherent X-ray Diffraction Workshop, BNL, May Quantitative Phase Measurement Average AFM height and reconstructed thickness for the four areas indicated in Fig 2(c). RegionAFM (nm)FCDI (nm) 1370 ± 8*360 ± ± 7377 ± ± ± ± ± 19 *Errors are estimated from the variance in the heights recovered within each region, as this includes intrinsic height variation the errors are therefore conservative. Clark, J.N., et al., Quantitative phase measurement in coherent diffraction imaging. Optics Express, (5) Use prior knowledge of the incident wave to recover the “exit surface wave” leaving the object
Coherent X-ray Diffraction Workshop, BNL, May What do we mean by “support”? Support is interpreted slightly differently here –the structure to be reconstructed is the coherent exit wave, including the illumination, not the scattering object itself.
Coherent X-ray Diffraction Workshop, BNL, May Optical Demonstration Diode Laser Beam Optical Test Chart CCD Camera
Coherent X-ray Diffraction Workshop, BNL, May
Independent Fresnel CDI images of a large object Experimental data obtained using coherent visible light
Coherent X-ray Diffraction Workshop, BNL, May X-Ray CDI
Coherent X-ray Diffraction Workshop, BNL, May
Have achieved a resolution of ~15nm! B Abbey et al, “ Keyhole Coherent Diffractive Imaging”, Nature Physics, Published on the web March 9, 2008
Coherent X-ray Diffraction Workshop, BNL, May Exceeds resolution of STXM with same optics, by a factor of ~4!
Coherent X-ray Diffraction Workshop, BNL, May Images of a fuse-bay sample
Coherent X-ray Diffraction Workshop, BNL, May All of the conceptual and methodological pieces are in place for us to achieve 3D imaging of extended objects with 5nm spatial resolution
Coherent X-ray Diffraction Workshop, BNL, May Collaborators Harry Quiney (UM)Harry Quiney (UM) Andrew Peele (La Trobe)Andrew Peele (La Trobe) Garth Williams (UM)Garth Williams (UM) Lachlan Whitehead (UM)Lachlan Whitehead (UM) Brian Abbey (UM)Brian Abbey (UM) Jesse Clark (La Trobe)Jesse Clark (La Trobe) David Paterson (Australian Synchrotron)David Paterson (Australian Synchrotron) Martin de Jonge (APS – Now AS)Martin de Jonge (APS – Now AS) Ian McNulty (APS)Ian McNulty (APS) Z Cai (APS)Z Cai (APS) Leann Tilley (La Trobe)Leann Tilley (La Trobe) Eric Hanssen (La Trobe)Eric Hanssen (La Trobe)