Bright spatially coherent synchrotron X-rays from a table-top source

Abstract

Betratron oscillations of electrons driven through a plasma by a high-intensity laser generate coherent X-rays. A new study demonstrates the intensity of these X-rays can be as bright as that generated by conventional third-generation synchrotrons, in a device a fraction of the size and cost. Each successive generation of X-ray machines has opened up new frontiers in science, such as the first radiographs and the determination of the structure of DNA. State-of-the-art X-ray sources can now produce coherent high-brightness X-rays of greater than kiloelectronvolt energy and promise a new revolution in imaging complex systems on nanometre and femtosecond scales. Despite the demand, only a few dedicated synchrotron facilities exist worldwide, in part because of the size and cost of conventional (accelerator) technology1. Here we demonstrate the use of a new generation of laser-driven plasma accelerators2, which accelerate high-charge electron beams to high energy in short distances3,4,5, to produce directional, spatially coherent, intrinsically ultrafast beams of hard X-rays. This reduces the size of the synchrotron source from the tens of metres to the centimetre scale, simultaneously accelerating and wiggling the electron beam. The resulting X-ray source is 1,000 times brighter than previously reported plasma wigglers6,7 and thus has the potential to facilitate a myriad of uses across the whole spectrum of light-source applications.