The storing and releasing of mechanical waves without energy loss sounds a bit out there; almost as if it is the foundational principle for some MCU/Tony Stark tech. However, researchers Andrea Alu, founding director of the Photonics Initiative at the Advanced Science Research Center at The Graduate Center, CUNY, and by Massimo Ruzzene, professor of Aeronautics Engineering at Georgia Tech, can assure you that it is a real thing.
In their recently published paper found in Science Advances, the duo breaks down their new and potentially revolutionary methodology. In short, their discovery will allow sound waves to be stored intact for as long as you want and released on demand. The new discovery has a host of applications that could end up changing a lot of your favorite technology for the better.
Now, if you don't know already, light and sound waves play a part in some of the common technologies found today. However, properly catching waves to store them for an indefinite period of time has been out of the question. However, now that it has been demonstrated as possible the discovery could go on to open the doors to energy harvesting, information storage, and quantum computing just to name a few.
"Our experiment proves that unconventional forms of excitation open new opportunities to gain control over wave propagation and scattering. By carefully tailoring the time dependence of the excitation, it is possible to trick the wave to be efficiently stored in a cavity, and then release it on demand towards the desired direction,” said Alù.
How did they do it?
To fully grasp the discovery we need to give you a little refresher. When a light or sound wave collides with an object it is either partially absorbed or reflected and scattered. When the waves are absorbed they are immediately converted to another form of energy, ie. heat. Think about what happens when you shine light too long on something at home. It gets very warm.
In short, the researchers devised a process where waves upon contact of an object stay waves rather than be converted to other forms of energy. Taking this idea, researchers would go to propagate two mechanical waves traveling in opposite directions along a carbon steel waveguide bar that contained a cavity.
Researchers were able to stop the excitation or detuning one of the waves. Even more so they were able to capture these waves and rerelease them to a direction of their choosing. In short, their findings will be applicable to “radio waves and light, offering exciting prospects for efficient energy harvesting, wireless power transfer, low-energy photonics, and generally enhanced control over wave propagation."