Duality of Quasilocal Black Hole Thermodynamics

We consider T-duality of the quasilocal black hole thermodynamics for the three-dimensional low energy effective string theory. Quasilocal thermodynamic variables in the first law are explicitly calculated on a general axisymmetric three-dimensional black hole solution and corresponding dual one. Physical meaning of the dual invariance of the black hole entropy is considered in terms of the Euclidean path integral formulation.Comment: 19 pages, Latex, no figures, to be published in Class. Quantum Grav. Some minor changes, references adde

Radial-tangential mode of single-wall carbon nanotubes manifested by Landau regulation: reinterpretation of low- and intermediate-frequency Raman signals

Abstract The low-frequency Raman signals of single-wall carbon nanotubes (SWNTs), appearing in the range of 100–300 cm−1, have been interpreted as radial-breathing mode (RBM) comprising pure radial Eigenvectors. Here, we report that most of the low-frequency and intermediate-frequency signals of SWNTs are radial-tangential modes (RTMs) coexisting radial and tangential Eigenvectors, while only the first peak at the low-frequency side is the RBM. Density functional theory simulation for SWNTs of ~ 2 nm in diameter shows that dozens of RTMs exhibit following the RBM (~ 150 cm−1) up to G-mode (~ 1592 cm−1) in order with Landau regulation. We specify the RBM and the RTM on Raman spectra obtained from SWNTs, where both appear as prominent peaks between 149 and 170 cm−1 and ripple-like peaks between 166 and 1440 cm−1, respectively. We report that the RTMs have been regarded as RBM (~ 300 cm−1) and ambiguously named as intermediate-frequency mode (300–1300 cm−1) without assignment. The RTMs gradually interlink the RBM and the G-mode resulting in the symmetric Raman spectra in intensity. We reveal high-resolution transmission microscope evidence for a helical structure of SWNTs, informing the typical diameter of commercial SWNTs to be 1.4–2 nm

Observation and Differentiation of Unique High-Q Optical Resonances Near Zero Wave Vector in Macroscopic Photonic Crystal Slabs

We demonstrate and distinguish experimentally the existence of a special type of Fano resonances at k≈0 in a macroscopic two-dimensional photonic crystal slab. We fabricate a square lattice array of holes in a silicon nitride layer and perform an angular resolved spectral analysis of the various Fano resonances. We elucidate their radiation behavior using temporal coupled-mode theory and symmetry considerations. The unique simplicity of this system whereby an ultralong lifetime delocalized electromagnetic field can exist above the surface and consequently easily interact with added matter, provides exciting new opportunities for the study of light and matter interaction.United States. Dept. of Energy. Office of Science (Grant DE-SC0001299)United States. Dept. of Energy. Office of Basic Energy Sciences (Grant DE-SC0001299)Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies (Contract Contract W911NF-07- D0004)National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Grant DMR- 0819762