Nanoscale ‘abacus’ uses pulses of light instead of wooden beads to perform calculations

The quest to develop ever-faster and more powerful computers has led to one of the most rudimentary methods of counting being given a 21st century make-over.

An international team of researchers, including Professor C. David Wright from the University of Exeter, have developed a nanoscale optical ‘abacus’ – which uses light signals to perform arithmetic computations.

The innovative device works by counting pulses of light – much in the same way beads are used to count when using a conventional abacus - before storing the data. This pioneering new technique could pave the way to new, more powerful computers that combine computing and storage functions in one element – a move away from conventional computers that treat these two functions as separate.

The study is published in leading scientific journal, Nature Communications.

Prof. C David Wright, an expert in electronic engineering and co-author of the study said: “This device is able to carry out all the basic functions you’d associate with the traditional abacus – addition, subtraction, multiplication and division – but what’s more it can do this using picosecond (one-thousandth of a billionth of a second) light pulses”.

Lead author of the study, Professor Wolfram Pernice from the Institute of Physics at Münster University in Germany added: “In the article we describe for the first time the realization of an abacus which operates in a purely optical way. Rather than wooden beads as found on traditional abacuses, our innovative device calculates with pulses of light – and simultaneously stores the result.”

The team’s optical abacus, which is so small it’s essentially invisible to the naked eye, is installed on a photonic microchip that can be easily manufactured. So far, the researchers have succeeded in calculating with two-digit numbers using two photonic phase-change cells, but the extension to large multi-digit numbers simply involves the use of more cells.

Co-author Professor Harish Bhaskaran, from the University of Oxford, added: “Computing with light – and not with electrons, as is the case with traditional computers - means that we can develop much faster systems which can be connected using integrated optical waveguides.”

Calculating with light using a chip-scale all-optical abacus is published in Nature Communications on Thursday, November 2 2017. It was funded by the German Research Foundation and the UK’s EPSRC.

Calculating with light using a chip-scale all-optical abacus J. Feldmann, M. Stegmaier, N. Gruhler, C. Ríos, H. Bhaskaran, C. D. Wright & W. H. P. Pernice Nature Communications 8, Article number: 1256 (2017) doi:10.1038/s41467-017-01506-3

University of Exeter

#Computing #Photonics




Flexible material shows potential for use in fabrics to heat, cool

Carbon-loving materials designed to reduce industrial emissions

The lightest shielding material in the world

Thermophones offer new route to radically simplify array design

Crystal wars

Laser takes pictures of electrons in crystals

Contactless way to measure thickness of carbon nanotube films