Technical Seminars
A series of Technical Seminars related to the APS Upgrade will be presented on the second and fourth Wednesdays during the summer months. The seminar topics were chosen to be of broad interest to the APS User Community with the purpose of providing the latest thinking on Upgrade-related topics. In addition, this seminar series also provides a forum for User feedback and comment on the direction and scope of these topics.
This Week
May 21
Tuesday
Tuesday
Lensless X-ray Imaging of Atomic Surface Structures in the Reflection Geometry using Ptychography
Speaker: Dr. Chenhiu Zhu, Materials Science Division, Argonne National LaboratoryXSD Presentation
401/A5000 @ 11:00 AM
View Description
Coherent x-ray diffraction imaging in the reflection geometry is desirable since it offers many advantages, including (1) lensless technique without need of object lenses, (2) few restrictions on sample size, chambers or environments, (3) suitable for studies of thin films grown on any substrates, (4) no need of pin holes near samples as in holography-based techniques, and (5) easily expandable to resonant coherent x-ray imaging.
We demonstrate by numerical simulation that atomic structures on single crystal surface can be reconstructed using the ptychography coherent x-ray diffraction imaging in the reflection geometry. Our approach is based on the concept of crystal truncation rod. We can obtain the highest surface sensitivity at anti-Bragg condition, and achieve a phase contrast up to from a single atomic step. Ptychograhy scanning scheme allows us to overcome the stringent requirement for isolated samples in typical CDI experiments. We will show experimental results from real platinum (001) surfaces and their ptychography reconstructions. This technique can be readily applied to buried interfaces under catalytic and electrochemical conditions and to nanoscience applications, such as nanowire with stacking faults.
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We demonstrate by numerical simulation that atomic structures on single crystal surface can be reconstructed using the ptychography coherent x-ray diffraction imaging in the reflection geometry. Our approach is based on the concept of crystal truncation rod. We can obtain the highest surface sensitivity at anti-Bragg condition, and achieve a phase contrast up to from a single atomic step. Ptychograhy scanning scheme allows us to overcome the stringent requirement for isolated samples in typical CDI experiments. We will show experimental results from real platinum (001) surfaces and their ptychography reconstructions. This technique can be readily applied to buried interfaces under catalytic and electrochemical conditions and to nanoscience applications, such as nanowire with stacking faults.
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Upcoming
May 29
Wednesday
Wednesday
Jun 5
Wednesday
Wednesday
Watching Microstructure Evolve
Speaker: Peter Voorhees, Northwestern UniversityAPS Colloquium
402/AUD @ 3:00 PM
Jun 7
Friday
Friday
Jun 14
Friday
Friday
Jun 21
Friday
Friday
Jun 28
Friday
Friday
Jul 20
Saturday
Saturday
ACA 2013
APS ConferenceHonolulu, Hawaii
Past Seminars
2010
Sep 8
Wednesday
Wednesday
APS Upgrade Technical Seminar: Nanoengineering and Nanopositioning
Speaker: Deming ShuAPS Seminar
CNM/A105 @ 10:00 AM
Aug 25
Wednesday
Wednesday
APS Upgrade Technical Seminar: Focusing Optics
Speaker: Lahsen AssoufidAPS Seminar
401/A1100 @ 10:00 AM
Aug 11
Wednesday
Wednesday
APS Upgrade Technical Seminar: IDs and FE Power Loadings
Speaker: Liz Moog and Patric Den HartogAPS Seminar
401/A1100 @ 2:30 PM
Jul 28
Wednesday
Wednesday
Jul 14
Wednesday
Wednesday
APS Upgrade Technical Seminar: BL Control Software and Software Infrastructure
Speaker: Pete Jemian and Claude SaundersAPS Seminar
401/A1100 @ 10:00 AM
Jun 23
Wednesday
Wednesday
APS Upgrade Technical Seminar: Computing/Network
Speaker: Ken SidorowiczAPS Seminar
401/A1100 @ 10:00 AM
Jun 9
Wednesday
Wednesday
APS Upgrade Technical Seminar: Long Straights, RHB and Overall Performance Specs
Speaker: Michael BorlandAPS Seminar
401/A1100 @ 10:00 AM