Soundwaves can control light.

Soundwaves can control light.

Soundwaves can control light. And that makes them new tools for making photonic computers. Soundwave is the denser point in the air. All changes in gas and other materials' density form a border layer. And that kind of border layers are changing the light's direction. 

Same way, the atmosphere around planets changes the direction of photons. If researchers make a chamber where there is gas and then aim the extremely sharp loudspeakers at that gas those soundwaves can aim laser rays in the desired direction. And that thing makes it possible to create a router. That aims laser rays into the wanted route. 

"A laser light beam passes between a loudspeaker-reflector array that creates a grating of air. The laser beam interacts with this grating and is deflected without contact. Credit: Science Communication Lab for DESY" (ScitechDaily.com/Sound Controls Light: Deflecting Laser Beams Using Air)

But laser light interacts oppositely way. When laser light hits medium it pumps energy to it. That energy makes atoms oscillate, and then that oscillation will travel all over the system. So when laser ray hits liquid like water it expands it. That expansion is the soundwave that can be used as sonar or even as a weapon. 

The laser can make a loudspeaker that uses liquids. When a laser ray hits liquid between membranes it expands that material. And that expansion is heard as soundwaves. 

When a laser satellite sends a laser ray to water or any other medium that thing sends sound waves. And other laser points around that center laser can observe that soundwave and its reflections. That thing makes it possible to search underwater and underground objects.  If the laser ray is strong enough it forms a similar situation with depth charge. 

"An intense laser pulse (in red) hits a flow of water molecules, inducing an ultrafast dynamics of the electrons in the liquid. Credit: Joerg M. Harms / MPSD" (ScitechDaily.com/Intense Lasers Illuminate the Hidden World of Electron Dynamics in Liquids)

Laser engine. 

The laser engine uses a liquid that is in the chamber. When a laser ray hits that liquid it expands it. And that expansion can push the piston down. In this case, the system can cool the liquid in the piston chamber if it is cooler with enough power. 

Or it can drive liquid or vapor from one chamber to another and rotate the turbine wheel in the channel between those chambers. Then that liquid can be cooled. And recycle in the system. 

The liquid can be liquid helium or nitrogen and the laser ray can interact with that liquid indirectly. In the non-direct version laser rays (or microwaves and electric arcs) are aimed into the expansion chamber. That warms the chamber's wall. 

That makes it possible to create the cold steam engine. This kind of system can operate without electricity if it has liquid nitrogen or helium. When that gas is in an expansion chamber there is no heat insulation. When it's at room temperature, the gas starts to expand. 

Lasers can increase the temperatures of some other objects like metal powder. Then that metal powder will drop into the chamber there is that ultra-cold liquid. 

That causes the expansion that can be used in turbine or piston engines. After that, the system can pull those metal bites with magnets to re-use. 

https://scitechdaily.com/intense-lasers-illuminate-the-hidden-world-of-electron-dynamics-in-liquids/

https://scitechdaily.com/sound-controls-light-deflecting-laser-beams-using-air/