Tools for imaging the interior of solid objects have come a long way since Wilhelm Röntgen accidentally discovered x rays and captured an image of his wife’s hand bones in 1895. Röntgen would likely be amazed by today’s synchrotron light sources, in which coherent beams of x rays scattered by an object can be used to reconstruct nanoscale structures such as crystals and biological macromolecules.
Bright beams of x rays that are emitted in a single direction onto the target of interest are difficult to come by in a laboratory setting. Unlike large-scale accelerators, which emit highly collimated beams, small-scale laboratory sources generate x rays in all directions. Once they’re emitted, x rays may be concentrated or redirected with mirrors, crystals, and lenses. However, collecting photons over a wide angular range and refocusing them onto a sample is hampered because, for x rays, the difference between the index of refraction...
