Giant SPIDERs etc.

Some good recent stuff in PRL:

Giant Surface-Plasmon-Induced Drag Effect in Metal Nanowires
Maxim Durach,1 Anastasia Rusina,1 and Mark I. Stockman1,2,3
Phys. Rev. Lett. 103, 186801 (2009)

Here, for the first time we predict a giant surface-plasmon-induced drag-effect rectification (SPIDER), which exists under conditions of the extreme nanoplasmonic confinement. In nanowires, this giant SPIDER generates rectified THz potential differences up to 10 V and extremely strong electric fields up to ~105–106 V/cm. The giant SPIDER is an ultrafast effect whose bandwidth for nanometric wires is ~20 THz. It opens up a new field of ultraintense THz nanooptics with wide potential applications in nanotechnology and nanoscience, including microelectronics, nanoplasmonics, and biomedicine.

[sg] I haven't read this paper and I'm not sure I want to, I'm just awed by the brilliance of "giant SPIDER effect." This is obviously going to collect oodles of citations, mostly from me.

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Holstein Polarons Near Surfaces
Glen L. Goodvin, Lucian Covaci, and Mona Berciu
Phys. Rev. Lett. 103, 176402 (2009)

We study the effects of a nearby surface on the spectral weight of a Holstein polaron, using the inhomogeneous momentum average approximation which is accurate over the entire range of electron-phonon (e-ph) coupling strengths. The broken translational symmetry is taken into account exactly. We find that the e-ph coupling gives rise to a large additional surface potential, with strong retardation effects, which may bind surface states even when they are not normally expected. The surface, therefore, has a significant effect and bulk properties are recovered only very far away from it. These results demonstrate that interpretation in terms of bulk quantities of spectroscopic data sensitive only to a few surface layers is not always appropriate.

[sg] The recent work on surface polarons is pretty interesting and it's something I'd like to get into at some point. It's primarily motivated by the recent glut of exptal work on heterostructures of strongly correlated materials; the interfaces often undergo substantial electronic and/or lattice reconstruction. Naturally these not-terribly-stable surfaces are morbidly sensitive to, e.g., the electrostatic force exerted by a moving electron.
I'm also curious about whether the authors are right about the interpretation of surface-based spectroscopic data.

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Phys. Rev. Lett. 103, 177002 (2009)
Evidence for Two Time Scales in Long SNS Junctions
F. Chiodi, M. Aprili, and B. Reulet

We use microwave excitation to elucidate the dynamics of long superconductor–normal metal–superconductor Josephson junctions. By varying the excitation frequency in the range 10 MHz–40 GHz, we observe that the critical and retrapping currents, deduced from the dc voltage versus dc current characteristics of the junction, are set by two different time scales. The critical current increases when the ac frequency is larger than the inverse diffusion time in the normal metal, whereas the retrapping current is strongly modified when the excitation frequency is above the electron-phonon rate in the normal metal. Therefore the critical and retrapping currents are associated with elastic and inelastic scattering, respectively.

[sg] In the traditional Josephson junction model (i.e. tilted washboard + friction), switching happens when the washboard's wells cease to be metastable and retrapping happens when the terminal velocity of a particle going down the washboard goes to zero. Retrapping depends on friction and switching doesn't, so you have a clean separation of energy scales. In long junctions things are generally messier because switching depends on heat transfer from a locally normal area to the rest of the wire, etc.; however, this paper manages to retrieve a rather nice separation of scales.