title: Tunneling spectroscopy of the elementary excitations in a one-dimensional wire.
abstract: The collective excitation spectrum of interacting electrons in one dimension has been measured by controlling the energy and momentum of electrons tunneling between two closely spaced, parallel quantum wires in a GaAs/AlGaAs heterostructure while measuring the resulting conductance. The excitation spectrum deviates from the noninteracting spectrum, attesting to the importance of Coulomb interactions. An observed 30% enhancement of the excitation velocity relative to noninteracting electrons with the same density, a parameter determined experimentally, is consistent with theories on interacting electrons in one dimension. In short wires, 6 and 2 micrometers long, finite size effects, resulting from the breaking of translational invariance, are observed.
authors.affiliation: Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel. ophir.auslaender@weizmann.ac.il
authors.forename: O M
authors.initials: OM
authors.lastname: Auslaender
authors.forename: A
authors.initials: A
authors.lastname: Yacoby
authors.forename: R
authors.initials: R
authors.lastname: de Picciotto
authors.forename: K W
authors.initials: KW
authors.lastname: Baldwin
authors.forename: L N
authors.initials: LN
authors.lastname: Pfeiffer
authors.forename: K W
authors.initials: KW
authors.lastname: West