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Utilization of Plasmonic and Photonic Crystal Nanostructures for Enhanced Micro- and Nanoparticle Manipulation
Published on: September 27, 2011
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Optical tweezers beyond refractive index mismatch using highly doped upconversion nanoparticles.
Xuchen Shan1, Fan Wang2,3, Dejiang Wang1
1Institute for Biomedical Materials & Devices (IBMD), Faculty of Science, University of Technology Sydney, Sydney, New South Wales, Australia.
Nature Nanotechnology
|February 19, 2021
Summary
This study introduces a new optical trapping technology using resonance effects in nanocrystals. It significantly enhances optical trapping forces for low-refractive-index nanoparticles, overcoming previous limitations.
Area of Science:
- Nanotechnology
- Optics
- Materials Science
Background:
- Optical tweezers rely on refractive index mismatch for trapping.
- Trapping low-refractive-index nanoscale objects is challenging.
- Existing methods struggle with nanoparticles and intracellular organelles.
Purpose of the Study:
- To develop a novel technology for enhanced optical trapping of low-refractive-index nanoscale objects.
- To overcome the limitations of refractive index mismatch at the nanoscale.
- To explore lanthanide doping for improved optical trapping capabilities.
Main Methods:
- Employing a resonance effect to enhance nanocrystal permittivity and polarizability.
- Utilizing highly doped lanthanide ions in NaYF4 nanocrystals.
- Investigating the Clausius-Mossotti factor under resonance conditions.
Main Results:
- Achieved optical trapping forces orders of magnitude greater than conventional methods.
- Demonstrated a maximum optical trap stiffness of 0.086 pN μm⁻¹ mW⁻¹ for 23.3-nm-radius nanoparticles (refractive index 1.46).
- Observed trapping forces over 30 times stronger than those for gold nanoparticles of similar size.
Conclusions:
- Lanthanide doping offers a new pathway for optical control of nanomaterial refractive indices.
- The technology enables optical force tagging for intracellular organelle manipulation.
- Potential integration with temperature sensing and laser cooling capabilities for optical tweezers.
