Scientists from MIT have created the first molecular clock on a chip. The clock relies on the constant, measurable rotation of molecules in order to keep time. The molecules rotate in this manner when exposed to a specific frequency of electromagnetic radiation. Experts believe that this chip could one day help to dramatically improve both the accuracy and performance of smartphone navigation.
Atomic clocks are the most accurate time-keepers known to man. When exposed to a specific frequency, the steady resonance of atoms allows the clock to measure out exactly one second. GPS satellites rely on such clocks. They triangulate time signals broadcasts from satellites using a method known as trilaterating. Unlike traditional triangulation, this method uses 3-D dimensional data for positioning.
Unfortunately, atomic clocks are bulky and costly. As a result, smartphone technology has to contend with a far less accurate internal clock for determining locations. Because it relies on three separate satellite signals for navigation, there is a significant margin for error. This can be reduced by adding additional satellites, but this solution comes with its own set of problems.
That’s where MIT’s Department of Electrical Engineering and Computer Sciences and Terahertz Integrated Electronics Group comes in. They’ve built an on-chip clock capable of exposing specific molecules to an ultrahigh frequency that makes them spin. Once the molecular rotations reach maximum energy absorption, a period output of a second is clocked. The resulting spin is consistent enough that it can act as a precise timing reference.
The molecular clock averaged an error of under one microsecond per hour. This means it is roughly 10,000 times more stable than the clocks found in smartphones. Since it’s fully electronic, the clock doesn’t rely on large, power-draining technology. As a result, it can be manufactured with the same low-cost integrated circuit technology found in all smartphone chips.
“Our vision is, in the future, you don’t need to spend a big chunk of money getting atomic clocks in most equipment. Rather, you just have a little gas cell that you attached to the corner of a chip in a smartphone, and then the whole thing is running at atomic clock-grade accuracy.”
The prototype needs some fine-tuning before it is commercialized. Scientists believe it can be made even smaller and more streamlined through further experimentation.
