778 research outputs found
Charge fluctuations and boundary conditions of biological ion channels : effect on the ionic transition rate
No full textA self-consistent solution is derived for the Poisson-Nernst-Planck (PNP) equation, valid both inside a biological ion channel and in the adjacent bulk fluid. An iterative procedure is used to match the two solutions together at the channel mouth. Charge fluctuations at the mouth are modeled as shot noise flipping the height of the potential barrier at the selectivity site. The resultant estimates of the conductivity of the ion channel are in good agreement with Gramicidin experimental measurements and they reproduce the observed current saturation with increasing concentration
Observation of the spin Nernst effect
No full textThe observation of the spin Hall effect triggered intense research on pure spin current transport. With the spin Hall effect, the spin Seebeck effect and the spin Peltier effect already observed, our picture of pure spin current transport is almost complete. The only missing piece is the spin Nernst (-Ettingshausen) effect, which so far has been discussed only on theoretical grounds. Here, we report the observation of the spin Nernst effect. By applying a longitudinal temperature gradient, we generate a pure transverse spin current in a Pt thin film. For readout, we exploit the magnetization-orientation-dependent spin transfer to an adjacent yttrium iron garnet layer, converting the spin Nernst current in Pt into a controlled change of the longitudinal and transverse thermopower voltage. Our experiments show that the spin Nernst and the spin Hall effect in Pt are of comparable magnitude, but differ in sign, as corroborated by first-principles calculations.QN/Nazarov GroupQN/Bauer Grou
Quantum Nernst Effect
No full textIt is theoretically predicted for the two-dimensional electron gas that the Nernst coefficient is strongly suppressed and the thermal conductance is quantized in the quantum Hall regime. The Nernst effect is the induction of a thermomagnetic electromotive force in the y direction under a temperature bias in the x direction and a magnetic field in the z direction. The quantum nature of the Nernst effect is analyzed with the use of edge currents and demonstrated numerically.research repor
Handbuch der anorganischen chemie : Unter mitwirkung von dr. Gadebusch, dr. Haitinger, dr. Lorenz, prof. dr. Nernst, dr. Philipp, prof. dr. Schellbach, prof. dr. von Sommaruga, dr. Stavenhagen, prof. dr. Zeisel, hrsg. von dr. O. Dammer.
No full textVol. 4 has title: Handbuch der anorganischen chemie, hrsg. von dr. O. Dammer. IV. band. Die fortschritte der anorganischen chemie in den jahren 1892-1902. Bearb. von ... dr. Baur ... dr. R. J. Meyer, prof. dr. Muthmann, dr. Nass, prof. dr. Nernst ... dr. Rothmund, dr. Stritar, prof. dr. Zeisel.Dates of publication: 1. bd., 1892; 2. bd., 1.-2. th., 1894; 3. bd., 1893; 4. bd., 1903.Physikalisch-chemische tabellen der anorganischen chemie. Von dr. Karl von Buchka. Ergänzungsband zu "O. Dammer's Handbuch der anorganischen chemie". Stuttgart, F. Enke, 1895. 348p.On t.-p. of v.2-3: Unter mitwirkung von dr. Benedict, dr. Gadebusch ... [etc.]."Synchronistische zusammenstellung der wichtigsten chemischen zeitschriften, bearb. von dr. Kaiser": v.1. p.[735]-745."Physikalische und theoretische chemie, unter mitwirkung von W. Nernst ergänzt von V. Rothmund": v.4, p.1-96."Allgemeiner theil, von dr. W. Nernst": v.1, p.1-358.Mode of access: Internet
Impurity Effect in the Quantum Nernst Effect
No full text"We theoretically study the Nernst effect and the Seebeck effect in a two-dimensional electron gas in a strong magnetic field and a temperature gradient under adiabatic condition. We recently predicted for a pure system in the quantum Hall regime that the Nernst coefficient is strongly suppressed and the thermal conductance is quantized due to quantum ballistic transport. Taking account of impurities, we here compute the Nernst coefficient and the Seebeck coefficient when the chemical potential coincides with a Landau level. We adopt the self-consistent Born approximation and consider the linear transport equations of the thermal electric transport induced by the temperature gradient. The thermal conductance and the Nernst coefficient are slightly modified from the pure case and the Seebeck coefficient newly appears because of the impurity scattering of electrons in the bulok states."research repor
Nernst effect in high-Tc superconducting films
No full textWe report measurements of the Nernst Effect in polycrystalline and epitaxial YBaCuO films. Such studies represent an important complement to Lorentz force experiments, since the thermal force is not subjected to spatial redistribution due to inhomogeneous flux pinning or damping. The Nernst effect also appears interesting for probing the superconducting fluctuation regime
Observation of the spin Nernst effect
No full textThe observation of the spin Hall effect triggered intense research on pure spin current transport. With the spin Hall effect, the spin Seebeck effect and the spin Peltier effect already observed, our picture of pure spin current transport is almost complete. The only missing piece is the spin Nernst (-Ettingshausen) effect, which so far has been discussed only on theoretical grounds. Here, we report the observation of the spin Nernst effect. By applying a longitudinal temperature gradient, we generate a pure transverse spin current in a Pt thin film. For readout, we exploit the magnetization-orientation-dependent spin transfer to an adjacent yttrium iron garnet layer, converting the spin Nernst current in Pt into a controlled change of the longitudinal and transverse thermopower voltage. Our experiments show that the spin Nernst and the spin Hall effect in Pt are of comparable magnitude, but differ in sign, as corroborated by first-principles calculations.</p
Einführung in die mathematische Behandlung der Naturwissenschaften : Kurzgefabtes Lehrbuch der Differential und Integralrechnung mit besonderer Berücksichtigung der Chemie
No full textMarca tip. na por
Kinetic modeling of Nernst effect in magnetized hohlraums
No full textWe present nanosecond time-scale Vlasov-Fokker-Planck-Maxwell modeling of magnetized plasma transport and dynamics in a hohlraum with an applied external magnetic field, under conditions similar to recent experiments. Self-consistent modeling of the kinetic electron momentum equation allows for a complete treatment of the heat flow equation and Ohm's law, including Nernst advection of magnetic fields. In addition to showing the prevalence of nonlocal behavior, we demonstrate that effects such as anomalous heat flow are induced by inverse bremsstrahlung heating. We show magnetic field amplification up to a factor of 3 from Nernst compression into the hohlraum wall. The magnetic field is also expelled towards the hohlraum axis due to Nernst advection faster than frozen-in flux would suggest. Nonlocality contributes to the heat flow towards the hohlraum axis and results in an augmented Nernst advection mechanism that is included self-consistently through kinetic modeling
Anomalous Nernst and Hall effects in magnetized platinum and palladium
No full textWe study the anomalous Nernst effect (ANE) and anomalous Hall effect (AHE) in proximity-induced ferromagnetic palladium and platinum which is widely used in spintronics, within the Berry phase formalism based on the relativistic band-structure calculations. We find that both the anomalous Hall (sigma(A)(xy)) and Nernst (alpha(A)(xy)) conductivities can be related to the spin Hall conductivity (sigma(S)(xy)) and band exchange splitting (Lambda(ex)) by relations sigma(A)(xy) = Delta(ex)e/(h) over bar sigma(S)(xy)(E-F)' and alpha(A)(xy) = -pi(2)/3 k(B)(2)T Delta(ex)/(h) over bar sigma(s)(xy)(mu)'', respectively. In particular, these relations would predict that the sigma(A)(xy) in themagnetized Pt (Pd) would be positive (negative) since the sigma(S)(xy) (E-F)' is positive (negative). Furthermore, both sigma(A)(xy) and alpha(A)(xy) are approximately proportional to the induced spin magnetic moment (m(s)) because the Delta(ex) is a linear function of m(s). Using the reported m(s) in the magnetized Pt and Pd, we predict that the intrinsic anomalous Nernst conductivity (ANC) in the magnetic platinum and palladium would be gigantic, being up to ten times larger than, e. g., iron, while the intrinsic anomalous Hall conductivity (AHC) would also be significant.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000336974800003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, Condensed MatterSCI(E)[email protected]
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