Sep 23 2019
Structured laser light has already paved the way for a wide range of applications. For example, it enables accurate machining, controlling, and trapping of materials, or defined movements of cell compartments or tiny particles.
A monolayer of organic molecules is placed in the focused light field and replies to this illumination by fluorescence, embedding all information about the invisible properties. (Image credit: © Pascal Rund)
Structured laser light also helps in maximizing the bandwidth of sophisticated, smart computing.
When a lens, such as a magnifying glass, is used as a burning glass to tightly focus these light structures, highly powerful three-dimensional (3D) light landscapes can be shaped. Such an approach will facilitate a considerably improved resolution in the mentioned applications. Light landscapes like these have opened the door for groundbreaking applications such as STED microscopy that received the Nobel Prize.
But these kinds of nano-fields are yet to be measured because components produced through tight focusing are not observed in standard measurement methods. So far, the lack of suitable metrological techniques has obstructed the advancement of nano-structured light landscapes as a tool for high-resolution imaging, optical tweezers, or material machining.
A research team around physicist and Professor Dr Cornelia Denz of the Institute of Applied Physics and chemist, Professor Dr Bart Jan Ravoo of the Center for Soft Nanoscience (SoN) from the University of Münster was able to create a nano-tomographic method.
This method has the potential to identify the usually invisible characteristics of nano-structured fields in a lens’ focus and eliminated the need for data post-processing or challenging analysis algorithms.
For this purpose, the researchers combined their know-how in the area of organic chemistry and nano-optics to achieve a method based on a single layer of organic molecules. This single layer is positioned in the focused light field and responds to this illumination through fluorescence, integrating all the data about the imperceptible characteristics.
When this response is detected, the nano-field is distinctly identified through a rapid and simple camera image.
This approach finally opens the till now unexploited potential of these nano-structured light landscapes for many more applications.
Dr Cornelia Denz, Study Head, Professor, Institute of Applied Physics, University of Münster
The study has been reported in the journal Nature Communications.
The research was supported by the Cells-in-Motion Cluster of Excellence and the Transregio Collaborative Research Centre 61 “Multilevel Molecular Assemblies: Structure, Dynamics and Function,” both at Münster University.