Physicists create the world's tiniest magnifying glass to see atomic bonds
And Trump's tiny hands
The world’s tiniest magnifying glass made with gold nanoparticles is powerful enough to see the individual chemical bonds between atoms, according to research published on Friday.
The energy of light can be measured by its wavelength, and it takes higher energies to see deeper into objects at smaller scales. By restricting light down to the order of nanometres, it can reveal the inner-workings of the atomic world that are normally hidden from the naked eye.
A paper published in Science [paywalled] shows that by tiny nanoparticles of gold can be used as a cavity to trap light below to less than a billionth of a metre.
Researchers led by the University of Cambridge call this tiny bump in the nanoparticle’s structure a “pico-cavity”.
The “pico-cavities” are small enough to hold a single molecule, and are formed by shining a laser beam over the gold nanoparticles. It’s a tricky process to control, and is only stable at cryogenic temperatures.
“We had to cool our samples to -260°C in order to freeze the scurrying gold atoms," said Felix Benz, lead author of the study and PhD student at the University of Cambridge, NanoPhotonics Centre.
The pico-cavities allow researchers to control and watch single atoms move in real time. The individual atoms sticking out “act like lightning rods” that “focus light instead of electricity”, according to the theoretical models studied by Javier Aizpurua, co-author of the study, and researcher at the Centre of Material Physics in San Sebastián, Spain.
If single atoms can be controlled, it opens up the possibility to manipulate chemical reactions with light, and it gives physicists a way to build complex molecules from smaller atoms.
More interestingly, perhaps, is that the picocavities could be used for data storage or as ultra-sensitive sensors. Information can be stored as molecular vibrations, and can be written and read with light. ®