Combining THz laser excitation with resonant soft X-ray scattering at the Linac Coherent Light Source

Abstract

This paper describes the development of new instrumentation at the Linac Coherent Light Source for conducting THz excitation experiments in an ultra high vacuum environment probed by soft X-ray diffraction. This consists of a cantilevered, fully motorized mirror system which can provide 600 kV cm À1 electric field strengths across the sample and an X-ray detector that can span the full Ewald sphere with in-vacuum motion. The scientific applications motivated by this development, the details of the instrument, and spectra demonstrating the field strengths achieved using this newly developed system are discussed.

The Linac Coherent Light Source

“…(iv) A whole suite of laser systems are needed across all LCLS instruments (Minitti et al, 2015), requiring the delivery of reliably tailored optical pulses in terms of wavelength, power, pulse duration, spatial profile and repetition rate, with precise control of time delay with respect to the LCLS pulses. This includes the development of laser-based secondary sources of excitation such as THz radiation that are requested for specific experiments (Turner et al, 2015).…”

Optical laser systems at the Linac Coherent Light Source

“…Since most of these applications require the sample to be in an ultra-high-vacuum environment, great care must be taken to guide the THz excitation pulse efficiently into the diffraction chamber. Interested readers are encouraged to read the article by Turner et al (2015) for a detailed description of the implementation of the soft X-ray THz instrument.…”

The Soft X-ray Research instrument at the Linac Coherent Light Source

“…This response can be attributed to the coherent rotation of the spin-cycloid plane by as much as 4 , and predicts that stronger THz pulses can rotate the magnetic polarization plane by as much as 90 . This work was carried out in the Resonant Soft X-ray Scattering endstation, which combines an in-vacuum diffractometer, cryogenic cooling capabilities and versatile configuration for laser in-coupling (Doering et al, 2011;Turner et al, 2015).…”