Archive for February 1st, 2012

Now we can really hear the grass growing…

Wednesday, February 1st, 2012 by Roberto Saracco

If you want to remark an exceptional hearing in English you use the sentence: “he can hear grass growing”. It is just a way of saying, the grass growing makes no sound, at least none that we can hear.

The tiniest ear...

But now scientist have invented a micro microphone that is able to detect the faintest sound we can imagine, and for the mike a grass growing creates a thunderous sound!

As reported in the Physical Letter researchers have managed to trap a gold nano particle between to laser beams. Such a particle is sensitive to sound waves as tiny as -60db. At this impossible weak sound pressure the particle oscillates and generates a variation in its kinetic energy at the level of 90microElectronV.

This sensitivity can let scientist explore the inner working of proteins in cells providing a better resolution of a living cell than the one possible by an electron microscope.

So, it is not something that will really provide us with super hearing, like the one of Superman, but even if it is confined to the labs it is interesting since it shows what kind of results can be achieved by mixing together different sciences, in this case optoelectronics and nanotechnology.

We are going to see more and more results stemming from this kind of cross-fertilization in this decade.