Squeezing Light for Ultra-Precise Measurements
Throughout history, many means of measurement have been used, including the common meter stick, the hand, and the micrometer. Which tool you use depends on the kind of measurement you are trying to make, including how precise you want the measurement to be. Thanks to the development of lasers, it is now possible to use light to measure distances, but at very small scales even light fails as the changes to it are not always detectable. Researchers at Griffith University and the University of Tokyo have successfully found a new way to measure quantum distances with light that works at such small sizes and even when the target is moving.
Typically the measurement is done by observing changes in the phase of the light, but these typical techniques have a limited ability to make precise measurements. What the researchers have done is squeezed the light to make changes to the phase much easier to detect. Squeezed light essentially takes advantage of the inequalities of the Heisenberg Uncertainty Principles by increasing the uncertainty in one, unimportant, property to approach certainty in another. In this case it is the phase which has its certainty improved.
The ability to make these ultra-precise measurements should prove very useful for the development of future nanoscale technologies. With the more precise data, the researchers working on that technology can create a more accurate theory of what is happening at that scale, which will lead to better tech.