Scientists from Case Western Reserve University have developed atomically thin devices capable of sending and receiving signals. What sets this creation apart is that the range of signals includes radio frequencies way beyond what the human ear is capable of hearing.
The device, called a drumhead, combines advanced technology with microscopic size. In fact, the drumhead is tens of trillion times smaller and over 100,000 times thinner than the apparatus that makes up the human eardrum. Researchers believe this technology will help in creating the next generation of ultra-low-power communications and sensory devices. Besides being significantly smaller than current devices, they will also have far greater tuning ranges and detection.
Miniaturization comes with its own set of challenges. Scientists have to work on achieving a broader dynamic range of detection. This range will need to be capable of picking up small signals like radio waves, sound, and vibration. Ultimately transducers that are capable of handling these signals are required. These transducers cannot run the risk of compromising information or losing it altogether.
Despite the wide variety of applications this device could have on the market, much of the research could prove useful for all manner of technology. The attention to limits, scaling, and measurement could prove particularly useful when it comes to transducers. These transducers could be a decade away, but the key components may be found in the atomic layer drumheads created during this experiment.
So how did scientists manage to create a device capable of such intense hearing prowess? Researchers exfoliated individual atomic layers from a bulk semiconductor crystal. A combination of nanofabrication and micromanipulation techniques was used to suspend atomic layers over micro-cavities pre-defined on a silicon wafer. Finally, electrical contacts are made to the device. These resonators are also extremely tunable, which means the tones can be easily manipulated. This is accomplished by stretching the drumhead membranes using electrostatic forces.
While this technology is just the beginning, it signifies an incredible step forward in auditory technology. These devices could soon be used to improve the quality of transducers and other technological devices.