New record on squeezing light to one atom: Atomic Lego guides light below one nanometer

All electronic devices consist of billions of transistors, the key building block invented in Bell Labs in the late 1940s. Early transistors were as large as one centimeter, but now measure about 14 nanometers. There has also been a race to further shrink devices that control and guide light. Light can function as an ultra-fast communication channel, for example, between different sections of a computer chip, but it can also be used for ultra-sensitive sensors or novel on-chip nanoscale lasers.

New techniques have emerged to confine light into extremely tiny spaces, millions of times smaller than current ones. Researchers previously found that metals can compress light below the wavelength-scale (diffraction limit), but more confinement would always come at the cost of more energy losses. This paradigm has now been shifted by using graphene.

In a recent study published in Science, ICFO researchers have now confined light down toa space one atom thick in dimension, the smallest confinement possible. The work was led by ICREA Prof at ICFO Frank Koppens and carried out by David Alcaraz, Sebastien Nanot, Itai Epstein, Dmitri Efetov, Mark Lundeberg, Romain Parret, and Johann Osmond from ICFO, and performed in collaboration with University of Minho (Portugal) and MIT (USA).