Sorry, you need to enable JavaScript to visit this website.
office.cense@iisc.ac.in | +91-80-2293 3276/ +91-80-2293 3291 | Sitemap

Role of Entropy in the Expulsion of Dopants from Optically Trapped Colloidal Assemblies

TitleRole of Entropy in the Expulsion of Dopants from Optically Trapped Colloidal Assemblies
Publication TypeJournal Article
Year of Publication2016
AuthorsKakoty, H, Banerjee, R, Dasgupta, C, Ghosh, A
JournalPhysical review letters
Volume117
Pagination258002
Abstract

Controlling an assembly of colloidal particles under external forces can be helpful in developing soft nanomaterials with novel functionalities. How external impurities organize within such confined systems is of fundamental and technological interest, especially when the system sizes are so small that even a single dopant can interact with an appreciable fraction of the system. To address this question, we use a defocused laser beam to form two-dimensional colloidal crystallites containing foreign dopants. Our studies reveal a surprising position dependence in the fate of dopants getting either spontaneously expelled or permanently internalized within the crystallite. This phenomenon arises due to the subtle interplay between the effects of external confinement and the role of entropy in the thermodynamics of small assemblies of interacting particles.

DOI10.1103/PhysRevLett.117.258002