In a recent development, physicists led by Dr. David Phillips at the University of Exeter have created a new method for trapping small particles with light.1
This advancement builds upon the Nobel Prize-winning optical tweezers technique pioneered by Arthur Ashkin in 2018, opening up exciting possibilities for precise particle manipulation across various fields.
Overcoming Limitations of Conventional Optical Tweezers
Conventional optical tweezers, while revolutionary, face challenges when trapping particles larger than 10 μm.
The Exeter team hypothesized that by enveloping the particle with light instead of concentrating it in the middle, they could achieve stronger confinement – like giving the particle a tight hug.
- Conventional tweezers use a tightly focused laser beam to attract and trap micro-sized particles or organisms
- Particles in optical tweezers experience thermal motion, constantly jiggling but confined to a certain volume
- Smaller confinement volumes generally make optical traps more useful
Crafting Custom “Suits of Light” for Each Particle
One key aspect of this new technique is that there’s no one-size-fits-all solution.
For optimal performance, each particle requires a tailored “suit of light”. The researchers collaborated with teams from the University of Glasgow and Vienna University of Technology to develop the necessary mathematical, numerical, and experimental methods to realize this.
Expanding Applications & Advancing the Field
The ability to trap irregularly shaped particles larger than 0.1 mm opens up new possibilities for optical tweezers.
This technique could be applied to:
- Living organisms like plankton and cultured cells
- Environmental samples such as microplastics, informing more effective pollution mitigation strategies
- Single-molecule biophysics, allowing measurement of nanometer-scale distances and piconewton-scale forces
- Studying interactions between proteins and DNA, energy landscapes of proteins, and kinetics of molecular motors
The research team’s innovative approach, detailed in their paper “Photon-efficient optical tweezers via wavefront shaping,”(ref) enables optical trapping without focusing any laser light onto the trapped particles. This breakthrough paves the way for the next generation of optical tweezers and their applications across biology, chemistry, and environmental science.
Collaboration & Funding Drive Innovation
The development of this new optical tweezers technique highlights the importance of collaboration across disciplines.
By bringing together expertise in physics, mathematics, and engineering, the research team pushed the boundaries of what’s possible with optical manipulation.
This work was made possible with funding from:
- European Research Council
- Royal Academy of Engineering
- Engineering and Physical Sciences Research Council
- Royal Society of Edinburgh
- Austrian Science Fund
The Future of Optical Manipulation
As researchers continue to refine and innovate upon this technique, we can expect to see even more impressive feats of particle control and analysis in the years to come.
From unraveling the mysteries of biology to developing new materials and technologies, optical tweezers will undoubtedly play a key role in shaping the future of science and innovation.
The development of bespoke optical tweezers is just one example of the rapid progress being made in the field of optical manipulation.
As the technology matures, efforts will likely focus on making optical tweezers more accessible and user-friendly for researchers across various fields, while also considering the ethical implications and ensuring responsible use of this powerful tool.
Source:
1. University of Exeter News
Read Next:
Martha A. Lavallie
Martha is a journalist with close to a decade of experience in uncovering and reporting on the most compelling stories of our time. Passionate about staying ahead of the curve, she specializes in shedding light on trending topics and captivating global narratives. Her insightful articles have garnered acclaim, making her a trusted voice in today's dynamic media landscape.