title: Reversibility and energetics in optical computing.
abstract: Computer operations that conserve energy do not, from an information viewpoint, increase entropy and therefore have no minimum energy cost associated with them. An information-conserving operation must be reversible in principle; reversible optical gates inevitably incur losses. The energy per calculation may have many meanings, as we show. The energy expended by a single photon in a conservative optical operation is negligible, much less than kT.
authors.forename: H J
authors.initials: HJ
authors.lastname: Caulfield
authors.forename: J
authors.initials: J
authors.lastname: Shamir
authors.forename: J E
authors.initials: JE
authors.lastname: Ludman
authors.forename: P
authors.initials: P
authors.lastname: Greguss