A new force for optical tweezers awakens

Illustration of an optical tweezer Credit: Giovanni Volpe

“We call it 'intra-cavity feedback force'. The basic idea is that, depending on where the particle or cell you want to study is, the amount of laser light used to trap it changes automatically. Whenever the particle is in focus, the laser switches off. When the particle tries to escape, the laser switches on again”, says Giovanny Volpe, senior lecturer at the Department of Physics, University of Gothenburg.

An optical tweezer is a focused laser beam that can trap particles. Previously, two different types of forces that emerge from this type of tool have been identified: gradient force (which means the particle goes against the intensity of the laser) and scattering force (where the particle is pushed towards the laser).

Giovanni Volpe and his team have discovered a third type of force in this realm, and a new way of constructing optical tweezers. These break-throughs are poised to greatly improve the study of single biological cells.

“With this method, as much as 100 times less light is needed, in some cases, compared to using a traditional optical tweezer,” Giovanni Volpe explains. “With less light, you cause less photo damage to the cell you are studying.”

This could be useful for studying any cell that is usually suspended in a solution – a blood cell or a yeast cell, for example – that a researcher would want to study over a long period of time.

“One of the main issues when using optical tweezers is that the light raises the temperature of the cell, which is damaging. A rise of 10 degrees might not be tolerable, but the rise of 0,1 degrees might be fine.

So using less light, and therefore limiting the rise in temperature, could make a huge difference. Experiments could be done in a more realistic manner in relation to the cell's natural life cycle,” says Giovanni Volpe.

###

The findings are published in Nature Communications.
Title: “Intracavity optical trapping of microscopic particles in a ring-cavity fiber laser”
Link: https://www.nature.com/articles/s41467-019-10662-7

Alle Nachrichten aus der Kategorie: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Zurück zur Startseite

Kommentare (0)

Schreib Kommentar

Neueste Beiträge

Endangered botanic predators

Globally, one fourth of carnivorous plants are threatened An international research team including botanist Andreas Fleischmann from SNSB-BSM has evaluated the Red List threat categories for all 860 known species…

The smallest particle sensor in the world

Styrian technological innovation – made in Graz TU Graz, ams and Silicon Austria Labs has developed a compact and energy-efficient sensor for mobile devices, which informs users in real time…

Nanostructures with a unique property

Nanoscale vortices known as skyrmions can be created in many magnetic materials. For the first time, researchers at PSI have managed to create and identify antiferromagnetic skyrmions with a unique…

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close