Temporal Coherence in Surface x-ray Standing Waves

TL;DR

This paper introduces a new method linking x-ray temporal coherence to surface x-ray standing wave analysis, enabling clearer interpretation of nanostructure surface features through analytical formulas and experimental validation.

Contribution

It provides a unified theoretical framework and experimental validation for using temporal coherence in XSW analysis of large nanostructures on surfaces.

Findings

Derived analytical formulas relating XSW intensity to coherence

Experimental demonstration with metal nanoparticles on Si surface

Enhanced interpretation of nanostructure surface features

Abstract

We present a unified elucidation for the role temporal coherence properties of x-rays in surface x-ray standing wave analysis, under total external reflection condition. Analytical formulas have been derived that provide a direct relation between the intensity distribution of x-ray standing wave (XSW) pattern and complex degree of coherence of the incoming x-rays. The novelty of the proposed method has been demonstrated experimentally together with the theoretical results for a real application by analyzing the distribution of metal nanoparticles on a Si mirror surface. Our results demonstrate that the modified XSW approach opens up an opportunity to unambiguously interpret structural studies of large dimension nanostructure materials of height 200nm (or more), deposited on a substrate surface.