title: Intrinsic Negative Mass from Nonlinearity.
abstract: We propose and provide experimental evidence of a mechanism able to support negative intrinsic effective mass. The idea is to use a shape-sensitive nonlinearity to change the sign of the mass in the leading linear propagation equation. Intrinsic negative-mass dynamics is reported for light beams in a ferroelectric crystal substrate, where the diffusive photorefractive nonlinearity leads to a negative-mass Schrödinger equation. The signature of inverted dynamics is the observation of beams repelled from strongly guiding integrated waveguides irrespective of wavelength and intensity and suggests shape-sensitive nonlinearity as a basic mechanism leading to intrinsic negative mass.
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.|Center for Life Nanoscience@Sapienza, Istituto Italiano di Tecnologia, 00161 Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Di Mei
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Caramazza
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Pierangeli
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.|Center for Life Nanoscience@Sapienza, Istituto Italiano di Tecnologia, 00161 Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Di Domenico
authors.affiliation: Applied Physics Department, Hebrew University of Jerusalem, 91904 Jerusalem, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Ilan
authors.affiliation: Applied Physics Department, Hebrew University of Jerusalem, 91904 Jerusalem, Israel.
authors.forename: A J
authors.initials: AJ
authors.lastname: Agranat
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Di Porto
authors.affiliation: Dipartimento di Fisica, Università di Roma "La Sapienza," 00185 Rome, Italy.|ISC-CNR, Università di Roma "La Sapienza," 00185 Rome, Italy.
authors.forename: E
authors.initials: E
authors.lastname: DelRe