Small­est heat en­gine yet

The Witness - Wheels - - MOTORING -

THE jour­nal Sci­ence re­ports Ger­man sci­en­tists have built the world’s small­est heat en­gine, us­ing only one atom.

Much big­ger heat en­gines have helped shape mod­ern so­ci­ety by trans­form­ing ther­mal en­ergy into me­chan­i­cal force.

The re­searchers, led by Pro­fes­sor Kil­ian Singer, now pro­fes­sor at the Univer­sity of Kas­sel, used a Paul trap to cap­ture a sin­gle elec­tri­cally charged cal­cium atom. This atom can be heated with the help of elec­tri­cally- gen­er­ated noise and cooled by us­ing a laser beam.

As a re­sult, the atom is sub­jected to a ther­mo­dy­namic cy­cle. This means that the par­ti­cle moves back and forth within the trap, thus repli­cat­ing the stroke of a typ­i­cal en­gine. The atom not only acts in the same way as an en­gine but also stores the en­ergy.

The re­searchers say their sin­gle par­ti­cle en­gine can gen­er­ate power of 10- 22 Watts and op­er­ates at 0,3% ef­fi­ciency. If scaled up, its out­put would be equiv­a­lent to that of a car en­gine. The cy­cle can also be re­versed to cool nano sys­tems.

The aim of nano- en­gine re­search is, how­ever, to pro­vide in­sight into ther­mo­dy­nam­ics at the sin­gle- par­ti­cle level, which is cur­rently a very hot topic in re­search. The VW Foun­da­tion funds the project. — WR.

Newspapers in English

Newspapers from South Africa

© PressReader. All rights reserved.