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Special Note - Transferring blog entries from previous layout.
Apologies for some errors while thew new site is getting updated.

Look out for new fixes in the new year.
See you in 2018! Happy



New paper in Advanced Optical Materials

Geng et al 2017 inside cover
**Update (12.01.17 - POM images fromYong's paper are selected for the inside cover of Advanced Optical Materials! Click the cover above to freely access the article online)

Congratulations to Yong on the publication in Adv. Opt. Mater. titled: “Through the Spherical Looking-Glass: Asymmetry Enables Multicolored Internal Reflection in Cholesteric Liquid Crystal Shells”!

Spheres of cholesteric liquid crystal generate dynamic patterns due to selective reflection from a helical structure subject to continuously curved boundaries. In this paper the patterns are investigated exclusively.

Click here for an extended layman's abstract summary written by Jan & some info about the curious Alice in Wonderland-like title Happy


We're hosting the next German Liquid Crystal Conference in March 2018!

We are officially hosting the 45th German Liquid Crystal Conference this coming March 2018!


This will be a two-day conference on the physics, chemistry, applications & any other aspects of liquid crystals, held at the University of Luxembourg from March 21-23, 2018.

This is exciting for our group because it's going to be the 3rd time we host an international conference & it will be the largest one we've done yet. We are currently in close collaborations with groups in Belgium, the Netherlands, & France (note: this is not in competition with the the current French LC & soft matter society meetings).

Please check out the website for registration below!

Also, our Facebook Page for frequent updates for this year's meeting @

(FYI - Early bird deadline for registration and payment is
16th of February 2018!)

Hope to see you for fun talks on LCs in good ole Lux. this coming March!


Welcome to Anupam Sengupta! - Anupam will join the UniLu faculty in physics & materials sci.


Anupam received the ATTRACT Starting Investigator Grant 2016-17 for his project MBRACE - Microbial Biophysics of Rapid Adaptation in Changing Environments - with Jan Lagerwall as the local promotor. 

Anupam Sengupta will join the University of Luxembourg starting in the summer 2018 as an Assistant Professor in the Physics and Materials Science Research Unit. Using a cross-disciplinary approach, MBRACE will interface physics, biology, mathematics and engineering to study biological systems under changing environments, with a particular focus on order and topology inherent in living matter. Anupam holds a Dual Degree in Mechanical Engineering from the Indian Institute of Technology Bombay, India. He received a PhD in Physics for the thesis on Liquid Crystal Microfluidics, which he carried out at the Max Planck Institute for Dynamics and Self Organization, Göttingen, Germany 2009-2012. After a short postdoc in Göttingen, Anupam moved to MIT as a Human Frontiers Cross-Disciplinary Fellow to work on biophysical processes in marine environments. Since fall 2015, he is based at the Institute of Environmental Engineering, ETH Zurich, Switzerland. Here, in addition to marine ecology, Anupam works on microbial behaviour under low and hyper gravity conditions, and looks at bacterial dynamics in natural and nature-inspired ecosystems.

Link to Anupam Sengupta’s website:

We hope to have future collaborations with him & his group once he arrives to Luxembourg!

/written by Anupam, with edits by CGR & JL/

New paper on organic functionalized nanoparticles in nematic LCs

(click the above image to access the article online)

Congratulations to Martin on the publication in J. Mater. Chem. C of his dielectric spectroscopy study “Why organically functionalized nanoparticles increase the electrical conductivity of nematic liquid crystal dispersions”!

This paper gives a first systematic study of how and why nanoparticle doping raises the electrical conductivity of thermotropic liquid crystals like the commonly studied 5CB. By a careful analysis of the dielectric spectra, he shows that the hydrodynamic radius of the ionic charge carrier is much smaller than the nanoparticles, ruling out the particles themselves as the source of conductivity. The ligand molecules are also not the reason, as is demonstrated by strong sonication of the dispersions, such that the ligands detached from the nanoparticles. While this causes nanoparticle aggregation and the loss of suspension stability, the effect on conductivity is negligible. The ligand shell is, however, partially responsible, because the ions giving rise to the conductivity increase are most likely remnants from the ligand-functionalized nanoparticle synthesis process. We propose that these ions are brought in with the ligand shell when the particles are dispersed in the 5CB. Interestingly, the ions appear not to be released in an isotropic and aromatic solvent such as toluene, which is often the host for commercial gold nanoparticle suspensions, but 5CB is an ideal host for their dissolution. The aliphatic ligand shell has a higher compatibility with 5CB than with toluene, thanks to the alkyl tail of 5CB, and at the same time the high polarity of the 5CB (due to the cyano group) allows better ion dissolution than in regular hexane. Finally, the nematic order of the 5CB solvent provides an anisotropic environment in which the ligands are stretched out preferentially along the director, making release of ligand-bound ions to the solvent more likely.