title: Universal Scaling of Robust Thermal Hot Spot and Ionic Current Enhancement by Focused Ohmic Heating in a Conic Nanopore.
abstract: A stable nanoscale thermal hot spot, with temperature approaching 100 °C, is shown to be sustained by localized Ohmic heating of a focused electric field at the tip of a slender conic nanopore. The self-similar (length-independent) conic geometry allows us to match the singular heat source at the tip to the singular radial heat loss from the slender cone to obtain a self-similar steady temperature profile along the cone and the resulting ionic current conductance enhancement due to viscosity reduction. The universal scaling, which depends only on a single dimensionless parameter Z, collapses the measured conductance data and computed temperature profiles in ion-track conic nanopores and conic nanopipettes. The collapsed numerical data reveal universal values for the hot-spot location and temperature in an aqueous electrolyte.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556-5637, USA.
authors.forename: Zehao
authors.initials: Z
authors.lastname: Pan
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556-5637, USA.
authors.forename: Ceming
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556-5637, USA.|School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556-5637, USA.
authors.forename: Hsueh-Chia
authors.initials: HC
authors.lastname: Chang