Bright Ideas: 9/8/21 — Laser Beams Now Visible In Vacuum, Can Also Sharpen Blur In Space Pics
By Abby Proch, Editor, Photonics Online
Once invisible within a vacuum, laser beams are now “visible” says a team of physicists with the University of Bonn, according to Phys.org. Lasers normally require particles to scatter and reflect light, so measuring beam propagation has proven problematic. But researchers conducting quantum optics experiments have found they can use the atoms themselves to locate and measure the laser beams.
The trick is to change the laser light with elliptical polarization. The change organizes atoms along a “conveyer belt of light,” making them easily measurable within a few thousandths of a millimeter. The newfound measurement method has sped up the teams’ workflow from several weeks to just one day, according to the report.
Meanwhile, a new adaptive-optics laser and novel chirping system is capable of sharpening blurry astronomical images captured by ground-based telescopes, claims EU-based consortium TOPTICA Projects. The group employs a narrow band 63-watt laser and, by quickly changing its tuning (i.e., chirping), scientists can create a brighter artificial “star” of excited sodium atoms that serves as a reference point to help reduce blur. Researchers say the technology, to be installed at the European Space Agency’s Optical Ground Station in Spain, could have implications in satellite optical communications.
In other laser-related news, Space X hasn’t had a Starlink satellite launch since June 30 and some were starting to speculate reasons for the hiatus. Now, we have the answer: laser crosslinks. All of the new Starlink satellites will include laser crosslinks that promote lower latency satellite-to-satellite communication over reliance on ground stations, said President and CEO Gwynne Shotwell at the Space Symposium, according to Space News.
Space X had been steadily adding satellites to its broadband constellation in the first half of 2021, and one launch in January took the first laser crosslinks into orbit. The next Falcon 9 rocket launch with the Starlink internet satellites is expected sometime in September.
In fiber optics news, scientists at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) claim they can redirect and even restore WAN data when it encounters cable damage or disruption, according to a press release. Fiber optic cable failure — from severe weather, accidents and even animal interference — can mean costly service disruptions. If CSAIL’s system, ARROW, succeeds outside a simulated environment, it holds promise to significantly reduce repair costs, say researchers.
And, since current network infrastructure models still rely on the “telephony mode” of preparing for the worst by building for the worst, ARROW could provide more elasticity and a more “seamless recovery from failures.” In addition, researchers claim ARROW could carry as much as 2.4 times the traffic without needing new fibers. One setback? The novel algorithm that powers the system is problematic because of its “N-P hardness in computational complexity theory.”
In environmental news, LED streetlights are harming caterpillar populations, according to research published in Science Advances. While anecdotal evidence has suggested all artificial light at night (ALAN) is harmful to insect populations, a group of etymologists in the U.K. claim their preliminary research has found that white LED streetlights cause "more pronounced" negative impacts on nocturnal caterpillar feedings than yellow sodium lamps. While LED lighting boasts greater efficiency, the group notes that its proliferation could have widespread ecological impacts and therefore called for more investigation.
Finally, in mergers and acquisitions, Ansys, an engineering simulation software firm, plans to acquire Zemax, an optical imaging system simulation company. According to the Pittsburgh Business Times, Ansys says the deal will allow it to integrate Zemax technology into its own microscale-sized Lumerical photonics product and human vision perception product. Earlier this year, Ansys also acquired Phoenix Integration, a model-based engineering systems software company.