Scientists have created a macroscopic tractor beam using laser radiation

(ORDO NEWS) — Tractor rays are intuitive. Matter and energy interact with each other in countless ways throughout the universe.

Magnetism and gravity are natural forces that can pull objects towards each other, so there’s a precedent of sorts.

But creating a true tractor beam is something else.

The tractor beam is a device. which can move an object over a distance. The idea comes from a 1931 science fiction story called IPC Space Hounds:

“There is such a thing as a beam screen, you kill joy, and there are also lifting beams or tractor beams – two things that I tried to drown out, and for which you cheer me up.

The Bronx cheered me up. The Titanians have had a tractor beam for ages – he sent me complete bullshit on it – and the Jovians have both.

We’ll get them in three days, and it should be pretty easy to turn off the opposite of the tractor, either the pusher or the down beam.”

If science fiction had anything to say about it, tractor rays would already be commonplace, and we could thank Star Trek and Star Wars for spreading them.

But the attracting rays already exist, although their reach is only microscopic.

Microscopic tractor beams are used in devices called optical tweezers. Optical tweezers use lasers to move microscopic objects such as atoms and nanoparticles. They are used in biology, nanotechnology and medicine.

These tractor beams act on microscopic objects, but are not strong enough to pull larger macroscopic objects.

Now a team of researchers have successfully demonstrated a macroscopic tractor beam. They published an article explaining their work in the journal Optics Express.

Its title is Macroscopic Laser Pulling Based on the Knudsen Force in Rarefied Gas and the lead author is Lei Wang from Qingdao University of Science and Technology in China.

“In previous studies, the light pulling force was too low to pull a macroscopic object,” Wang said.

“With our new approach, the attractive force of light has a much greater amplitude. In fact, it’s more than three orders of magnitude greater than the light pressure used to drive a solar sail, which uses the momentum of photons to create a small pushing force.”

Scientists have created a macroscopic tractor beam using laser radiation

This macroscopic tractor beam only works under certain laboratory conditions, so this is a demonstration and not a practical development. At least for now.

First, he works with specially made things: macroscopic graphene-SiO 2 composite objects that the researchers built for experiments.

Secondly, it works in a rarefied gaseous medium, the pressure in which is much lower than in the Earth‘s atmosphere. Although this limits their effectiveness here on Earth, the atmospheric pressure on all worlds is not the same as on our planet.

“Our technique provides a non-contact long-distance pulling method that can be useful for various scientific studies. Experiments,” Wang said.

“The rarefied gas environment we used to demonstrate the technique is similar to that found on Mars. Therefore, she may have the potential to drive vehicles or aircraft on Mars. ”

Their device works on the principle of gas heating. The laser heats composite objects, but one side is hotter than the other.

The gas molecules on the other side receive more energy, which attracts the object. Combined with the lower pressure in the rarefied gas environment, the object moves.

The researchers built a torsional – or rotating – pendulum device made from their graphene-SiO 2 composite structure to demonstrate the laser stretching phenomenon.

This demonstration made it visible to the naked eye. They used a different device to measure the effect.

“We found that the attractive force is more than three orders of magnitude greater than the light pressure,” Wang said.

“In addition, the attraction of the laser is repeatable, and the strength can be adjusted by changing the power of the laser.”

In recent years, other researchers have been working on tractor rays with mixed results. NASA was interested in pursuing the idea of ​​using tractor beams to collect samples with the MSL Curiosity ground rover. One of Curiosity’s tools is ChemCam.

It involves a laser that vaporizes the rock or regolith and then a microvisor to measure its components spectroscopically.

But NASA wondered if a tractor beam could draw tiny particles from the vaporized sample into the rover for a more complete study.

A 2010 NASA presentation to NIAC stated: “If tractor beam technology was incorporated into ‘ChemCam2’ to draw in dust and plasma particles, tractor beams could add a set of additional scientific capabilities:

  • Laser desorption ion spectroscopy
  • Mass spectrometry
  • Raman spectroscopy
  • X-ray fluorescence

The same presentation said that tractor rays could be used to collect particles from comet tails, ice plumes on Enceladus, and even clouds. in the Earth’s atmosphere or other atmospheres.

This was never implemented, but shows how attractive the idea is.

This new study has yielded interesting results, although not close to actual practical implementation. It takes a lot of work and engineering before it even comes close to being practical.

First, there must be a well-understood theoretical framework describing how the effect works on objects of different sizes and shapes and with lasers of different powers in different atmospheres.

The researchers are aware of this, of course, but note that this is still an effective demonstration of feasibility.

“Our work demonstrates that flexible control of the light of a macroscopic object is possible when the interactions between light, object, and environment are carefully controlled,” Wang said.

“It also shows the complexity of laser-matter interactions and that many phenomena are far from being understood at both the macro and micro scales.”

The important point is that this study moves the attracting rays from the microscopic to the macroscopic. This is a significant threshold that is difficult to cross.

“This work extends the possibilities of optical attraction from the microscale to the macroscale, which has great potential in macroscale optical manipulations,” the authors write in their conclusion.

In the future, spaceships may well use tractor beams, but they are unlikely to look like science fiction. Star Wars, Star Trek, and S Pacehounds of IPC use tractor beams in combat and conflict.

But in fact, they can be valuable scientific tools.


Contact us: [email protected]

Our Standards, Terms of Use: Standard Terms And Conditions.