XDL2011 Workshop 5

Materials Science with Coherent Nanobeams at the Edge of Feasibility
Monday, June 27th - Tuesday, June 28th, 2011

---

Organizers: Christian Riekel (European Synchrotron Radiation Facility), Simon Billinge (Columbia University), Kenneth Evans-Lutterodt (Brookhaven National Laboratory), & Detlef Smilgies (Cornell University)

Workshop Agenda (html)

---

Purpose: Modern synchrotron radiation sources have demonstrated the scientific potential of combining the full spectrum of x-ray scattering techniques with micrometer and nanometer-size x-ray beams to study complex hierarchical, multi-component or inhomogeneous materials. Energy Recovery Linac (ERL) and Ultimate Storage Ring (USR) microbeams will be quasi-continuous and highly suitable to probe materials both in real and reciprocal space simultaneously, providing access to a much wider range scale than can be achieved with a single method (nanobeams only, scattering only). In particular, these advanced photon sources will be diffraction-limited, which will make it possible to close the gap between scanning and scattering resolution.

The envisioned workshop will cover selected areas at the forefront of the technology:

Nanobeam preparation
Nanobeam fluorescence imaging and analytics
Nanobeam diffraction - hard materials/ materials science
Nanobeam scattering - soft and biologic materials
Nanobeam coherent imaging

Description: Microbeams and nanobeams will be omnipresent in new sources such as energy-recovery linacs (ERL) and ultimate storage rings (USR). The present workshop will focus on frontier areas of the production and application of ultrafine x-ray beams that will open up science in area that can just barely be reached with current sources.

1. Nanobeam preparation. New high-brilliance sources such as ERLs and USRs provide beams with very small source points as well as with low divergence. This will allow focusing of a large part of the emitted radiation into the focal spot. Leading optical focusing methods comprise Fresnel zone plates, multilayer Laue lenses, compound and kinoform refractive lenses as well as multilayer KB mirrors.
2. Spectroscopic applications of nanobeams comprise fluorescence imaging and tomography as well as nanoXANES. The theoretical detection limit for a 1 nm beam is 1 zeptogram or the mass of a single atom. Applications range from environmental and planetary science to arts and archeology.
3. In hard matter science diffraction and standing waves will facilitate probes of strain in very small areas around single crystal defects or in single grains. Amorphous and nanocrystalline structures can be analyzed locally, maybe in combination with coherent diffraction imaging (CDI) methods.
4. In the life sciences and soft materials, scattering of low-divergence nanobeams will make information in heterogeneous and hierarchical materials accessible. As beams are close to the diffraction limit, it will be possible to close the resolution gap between scanning and scattering.
5. The high coherence of ERL and USR nano- and microbeams will start to blur the distinction of scattering and imaging. Speckles will be expected in many applications. Using state-of-the-art CDI methods, the information in the speckle patterns can be recovered.
6. Working with nanobeams will impose stringent conditions on positioning accuracy, temperature stability and vibration insulation of source, optics, and sample stage. New types of sample environments and sample metrology will be necessary to aim nanobeams properly and reduce unwanted background.

Science with nanobeams will open up new experimental areas, but also present formidable experimental challenges. The goal of work shop will be to investigate these challenges in selected areas at the scientific frontier.

Workshop contributions: Presentations will cover the preparation and application of nanobeams in hard condensed matter, soft condensed matter and biology, as well as in analytical techniques such as energy & environment sciences and art & archeology using hard x-ray nanometer-scale X-ray beams. Presentations will focus on the advantages and disadvantages of brilliance, source size, time structure, coherence and other characteristics of the ERL and USR beams.

Method: The workshop will occur at Cornell's Robert Purcell Center on June 27-28, 2011 and is open to anyone who may be interested. The workshop will start with a short overview of ERL and USR specifications and capabilities for frontier science with nanometer hard x-ray beams (see accompanying attachment for some ERL/USR background). The program, outlined below, will then continue with a core group of invited world-leaders to give short talks and lead the discussion in the relevant science areas. In order to allow time for discussion after each talk, speakers are asked to rigorously adhere to the 20 minute time limit. There will be ample additional time for open discussion and poster sessions. Workshop participants are especially encouraged to be inventive and explore unorthodox ideas.

Poster Session: There will be space to put up poster of up to 4'(height) x 6'(width) [1.2 x 1.8 meters]. If you plan to have a poster, please submit a ½ page abstract to Laura Houghton at lab49@cornell.edu and she will try to compile them into the program. There is a specific poster session time shown in the program, but they can remain up for the entire duration of the workshop.

Workshop Results: Our goal is to communicate the possibilities for science with an ERL or USR, as well as with other sources, and engage the community in developing ideas for the science case. Imaginative thinking will be required -- that's why we are assembling this workshop group! Documenting the results of the workshop is essential. We hope to explore compelling science that is uniquely enabled by an ERL or USR. Accordingly, each invited participant will be asked to present at least one novel experiment of interest (described by a 1-3 paragraphs of text, an appropriate graphic, and relevant references) that would be very difficult to perform without the capabilities of an ERL or USR. Time will be provided towards the end of the workshop to summarize results and conclusions.

Of particular importance is the group discussion at the end of the meeting. It is therefore very important that all invited workshop attendees stay through to the end of the workshop. It is in this period that our discussion leaders will try to pull all the good ideas generated into a summary and we need your very active participation to do this well. As a motivator to stay through to the end and to further the development of "community" for this brief several day period, we have arranged a series of excursions. Depending on the workshop these include, for example, Cayuga Lake Boat dinner cruises, local winery tours, visits to Ithaca's local spectacular gorge parks, etc.