From smartphones to quantum computers, modern technology depends on moving information quickly and efficiently. Now, scientists have found a way to control vibrations at gigahertz (GHz) speeds—inside microscopic drumhead structures—to serve as ultra-fast bridges between mechanical, microwave and optical signals.
Gigahertz (GHz) resonances and oscillations are very important carriers of information and energy, which are key to the functions of many information processing chips and systems. Nowadays, researchers have found a way to harness GHz vibrations—on the order of billion cycles per second—in highly miniature and ultra‑light drumhead resonators, with diameters on the order of one-tenth of that of human hair, and as thin as a few molecules. These high-speed oscillations are the invisible highways that translate signals between mechanical, microwave, and optical realms.
Traditionally, creating such GHz vibrations often required excitation of bulk or surface acoustic modes in much larger structures of special crystalline materials. The breakthrough promises to bring high quality-factor (high-Q) GHz modes in ultrasmall and ultralight resonators made of atomic layers, for the first time.
In a paper released today in Science Advances, Philip Feng, Ph.D., at the University of Florida and his co-authors demonstrated that tiny drumheads made of graphene and molybdenum disulfide (MoS₂), both hallmarks of 2D crystals widely used in emerging semiconductors, optoelectronics, and energy technologies, can sustain these fast oscillations with impressively high-Qs, even at room temperature.