ABSTRACT
Layered van der Waals materials of the family TaTMTe4 (TM = Ir, Rh, Ru) are showing interesting electronic properties. We report the growth and characterization of TaIrTe4, TaRhTe4, TaIr1-xRhxTe4 (x = 0.06, 0.14, 0.78, 0.92), Ta1+xRu1-xTe4 single crystals. X-ray powder diffraction confirms that TaRhTe4 is isostructural to TaIrTe4. All these compounds are metallic with diamagnetic behavior. Below T ≈ 4 K we observed signatures of the superconductivity in the TaIr1-xRhxTe4 compounds for x = 0.92. All samples show weak quadratic-in-field magnetoresistance (MR). However, for TaIr1-xRhxTe4 with x ≈ 0.78, the MR has a linear term dominating in low fields that indicates the presence of Dirac cones in the vicinity of the Fermi energy. For TaRhTe4 series the MR is almost isotropic. Electronic structure calculations for TaIrTe4 and TaRhTe4 reveal appearance of the Rh band close to the Fermi level.
ABSTRACT
Modeling and investigating the thermalization of microscopic objects with arbitrary shape from first principles is of fundamental interest and may lead to technical applications. Here, we study, over a large temperature range, the thermalization dynamics due to far-field heat radiation of an individual, deterministically produced silica fiber with a predetermined shape and a diameter smaller than the thermal wavelength. The temperature change of the subwavelength-diameter fiber is determined through a measurement of its optical path length in conjunction with an ab initio thermodynamic model of the fiber structure. Our results show excellent agreement with a theoretical model that considers heat radiation as a volumetric effect and takes the emitter shape and size relative to the emission wavelength into account.
ABSTRACT
We experimentally realize a Fabry-Perot-type optical microresonator near the cesium D2 line wavelength based on a tapered optical fiber, equipped with two fiber Bragg gratings that enclose a subwavelength diameter waist. Owing to the very low taper losses, the finesse of the resonator reaches F=86 while the on-resonance transmission is T=11%. The characteristics of our resonator fulfill the requirements of nonlinear optics and cavity quantum electrodynamics in the strong coupling regime. These characteristics, combined with the demonstrated ease of use and advantageous mode geometry, open a realm of applications.
