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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Emergent properties in optically bound matter
J M Taylor1, L Y Wong, C D Bain
1Department of Physics, Durham University, South Road, Durham DH1 3LE, UK. j.m.taylor@dur.ac.uk
Optics Express
|June 12, 2008
Summary
Large numbers of optically-trapped particles form unique 2D structures. Collective particle behavior changes, with optical binding forces overcoming laser field patterns to create new structures.
Area of Science:
- Physics
- Optical physics
- Soft matter physics
Background:
- Sub-micron particles can self-assemble into ordered structures.
- Optical trapping utilizes laser fields to confine particles.
- Interference patterns in laser fields create optical landscapes.
Purpose of the Study:
- To investigate the collective behavior of optically-trapped sub-micron particles.
- To explore how particle number influences self-assembled structures.
- To understand the role of optical binding forces in structure formation.
Main Methods:
- Computer modeling of particle interactions in laser fields.
- Experimental manipulation of sub-micron particles using counterpropagating evanescent laser fields.
- Analysis of structural changes with increasing particle numbers.
Main Results:
- Observed spontaneous formation of regular two-dimensional structures.
- Demonstrated that collective properties differ significantly from small numbers.
- Showed optical binding forces can dominate over laser-imposed landscapes.
- Identified the emergence of competing structures driven by particle interactions.
Conclusions:
- The collective behavior of optically-trapped particles is scale-dependent.
- Optical binding forces play a crucial role in dictating emergent structures.
- Particle self-assembly can lead to novel structures beyond the initial optical potential.
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