UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Optical trapping and optical force positioning of two-dimensional materials

Donato, MG; Messina, E; Foti, A; Smart, TJ; Jones, PH; Iati, MA; Saija, R; ... Marago, OM; + view all (2018) Optical trapping and optical force positioning of two-dimensional materials. Nanoscale , 10 (3) pp. 1245-1255. 10.1039/c7nr06465a. Green open access

[thumbnail of Article]
Preview
Text (Article)
nanoscaleAcceptedVersionNoFormatting.pdf - Accepted Version

Download (5MB) | Preview
[thumbnail of Supplementary Information]
Preview
Text (Supplementary Information)
nanoscaleAcceptedVersionNoFormatting-SuppInfo.pdf - Accepted Version

Download (651kB) | Preview

Abstract

In recent years, considerable effort has been devoted to the synthesis and characterization of two-dimensional materials. Liquid phase exfoliation (LPE) represents a simple, large-scale method to exfoliate layered materials down to mono- and few-layer flakes. In this context, the contactless trapping, characterization, and manipulation of individual nanosheets hold perspectives for increased accuracy in flake metrology and the assembly of novel functional materials. Here, we use optical forces for high-resolution structural characterization and precise mechanical positioning of nanosheets of hexagonal boron nitride, molybdenum disulfide, and tungsten disulfide obtained by LPE. Weakly optically absorbing nanosheets of boron nitride are trapped in optical tweezers. The analysis of the thermal fluctuations allows a direct measurement of optical forces and the mean flake size in a liquid environment. Measured optical trapping constants are compared with T-matrix light scattering calculations to show a quadratic size scaling for small size, as expected for a bidimensional system. In contrast, strongly absorbing nanosheets of molybdenum disulfide and tungsten disulfide are not stably trapped due to the dominance of radiation pressure over the optical trapping force. Thus, optical forces are used to pattern a substrate by selectively depositing nanosheets in short times (minutes) and without any preparation of the surface. This study will be useful for improving ink-jet printing and for a better engineering of optoelectronic devices based on two-dimensional materials.

Type: Article
Title: Optical trapping and optical force positioning of two-dimensional materials
Open access status: An open access version is available from UCL Discovery
DOI: 10.1039/c7nr06465a
Publisher version: http://doi.org/10.1039/c7nr06465a
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Brain Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Brain Sciences > Institute of Ophthalmology
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy
URI: https://discovery.ucl.ac.uk/id/eprint/10044495
Downloads since deposit
295Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item