New design lets micro-clock resonators ring like a bell

You can’t hear most of them, but the world is running on different kinds of mechanical oscillations. For example, inside the average electronic wristwatch is a sealed canister containing a 3 mm long quartz crystal resonator. In response to electrical feedback, the crystal continuously vibrates about 33,000 times per second. The remarkable stability of that resonance frequency, which provides the clock’s “tick” rate, keeps you on time.