All computational chips transmit and process data by modulating a certain medium. In our familiar computer processors, this medium is electric current, the movement of electrons, which is modulated by means of transistors. Photon processors modulate flows of photons, which circulate through special thin channels called light guides. And recently, scientists from Harvard University demonstrated a new kind of chip, which allows the operation of data encapsulated in the modulation of acoustic (sound) vibrations.
The acoustic type functions much like a photonic chip, only using acoustic waves instead of light. A device made of lithium niabat, a material that changes its elasticity in response to a change in the applied electric field, is used as a modulator to produce acoustic oscillations. By adjusting the parameters of the electric field, it is possible to control with high precision the phase, amplitude, and frequency of the generated acoustic waves, which allows data to be encoded in them and directed into the desired waveguide.
Scientists state that the chip that uses sound waves has a number of advantages over chips that use electromagnetic waves of various types, including light. The propagation of acoustic waves is easily confined to the space of the waveguide, they have almost no effect on each other, but they provide strong enough interactions with other parts of the system specifically designed for it.
“Acoustic waves can do a lot in the field of information transfer media for classical and quantum computing technologies. However, the emergence of acoustic processors has long been hampered by the lack of technology for high-precision control of sound waves and their low-loss transmission,” says Marko Loncar, lead researcher. “In our work, we have demonstrated that acoustic waves can be controlled with special lithium niobate devices, and this brings us one step closer to creating real acoustic processors and other integrated circuits.”
After creating the first prototype acoustic chip, the researchers went on to develop more complex acoustic systems and research aimed at integrating such systems with some components of quantum computing systems, with superconducting qubits in particular.
