title: Onset of optical-phonon cooling in multilayer graphene revealed by RF noise and black-body radiation thermometries.
abstract: We report on electron cooling power measurements in few-layer graphene excited by Joule heating by means of a new setup combining electrical and optical probes of the electron and phonon baths temperatures. At low bias, noise thermometry allows us to retrieve the well known acoustic phonon cooling regimes below and above the Bloch-Grüneisen temperature, with additional control over the phonon bath temperature. At high electrical bias, we show the relevance of direct optical investigation of the electronic temperature by means of black-body radiation measurements. In this regime, the onset of new efficient relaxation pathways involving optical modes is observed.
authors.affiliation: Laboratoire Pierre Aigrain, Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre et Marie Curie-Sorbonne Universités, Université Paris Diderot-Sorbonne Paris Cité, 24 rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: D
authors.initials: D
authors.lastname: Brunel
authors.forename: S
authors.initials: S
authors.lastname: Berthou
authors.forename: R
authors.initials: R
authors.lastname: Parret
authors.forename: F
authors.initials: F
authors.lastname: Vialla
authors.forename: P
authors.initials: P
authors.lastname: Morfin
authors.forename: Q
authors.initials: Q
authors.lastname: Wilmart
authors.forename: G
authors.initials: G
authors.lastname: Fève
authors.forename: J-M
authors.initials: JM
authors.lastname: Berroir
authors.forename: P
authors.initials: P
authors.lastname: Roussignol
authors.forename: C
authors.initials: C
authors.lastname: Voisin
authors.forename: B
authors.initials: B
authors.lastname: Plaçais