Dynamic x-ray optics with microfluidics: stabilization of gas bubbles by surface ordering and freezing

Optique dynamique RX avec des microfluides: Stabilisation des bulles de gaz par arrangement et réfrigération de surface

¹ Max Planck Institute for Dynamics and Self-Organization, 37073 Goettingen, Germany
² Ian Wark Research Institute, University of South Australia, South Australia 5095, Australia
³ Max Planck Institute for Dynamics and Self-Organization, 37073 Goettingen, Germany Experimental Physics, Saarland University, 66041 Saarbruecken, Germany

Corresponding authors: yasutaka.iwashita@ds.mpg.de christian.bahr@ds.mpg.de Craig.Priest@unisa.edu.au tephan.herminghaus@ds.mpg.de ralf.seemann@ds.mpg.de

Abstract

Compound refractive lenses (CRL), which are composed of many lenses aligned along the optical axis, have been developed as refractive x-ray optics. A CRL has numerous desired properties: It is robust, easy to align and to operate, and can be used for hard x-rays. To broaden the possibilities and functions of static CRL, we propose a "dynamic CRL", which is composed of continuously renewed gas bubbles in a surrounding liquid phase flowing along a thin capillary. Due to the continuous renewal, this system is expected to have a high stability against high x-ray intensities. Furthermore, the variation of the bubble volume and bubble shape by adjusting the flow parameters allows in-situ optimization of the optical properties of the system, i.e. the focal length. Here, we study the usage of liquid crystals and n-alkanes to be used in dynamic CRL's. These liquids have a very low x-ray absorption and the liquid - gas systems can be stabilized without surfactants using the surface ordering of liquid crystals respectively the surface freezing of n-alkanes