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Abstract: We investigated the dispersion property of a slab waveguide with an anisotropic metamaterial core whose permittivity tensor is partially negative. The subwavelength guidance characteristics are presented based on the boundary conditions. The results show that, at some specific frequencies, many high-order modes can exist in present waveguide even with the thickness of the guiding core 10 times smaller than the working wavelength. It is also found that different orientations of the optical axis of the anisotropic core will lead to different dispersion of the guided modes. If the orientation of the optical axis is properly chosen, the guided modes show a transition from backward wave to a forward wave as the frequency increases. During this transition, the group velocity of some guided modes can approach zero. Since the anisotropic metamaterial we discuss here can be fabricated in GHz, near- and mid-infra-red frequencies, our result may find some applications in wave trapper, integrated optical and nanophotonic devices. [Copyright &y& Elsevier]

Abstract: We present the first study of the hybridizing effect of different left-handed metamaterials (LHM) based on S-shaped and Ω-shaped resonators. Three different cases of hybridizing are investigated, ten configurations of various hybrid ratio are simulated, fabricated and measured, and a series of different left-handed passbands is obtained, showing that the left-handed passband of the proposed hybrid structure can be controlled by tuning the hybrid ratio. The hybrid left-handed metamaterial proposed in this Letter has potential applications in LHM-based filters, couplers, antennas, etc. [Copyright &y& Elsevier]

The tribological performance of Mn.P coating and PC/MoS 2 coating was investigated and compared with that of the reference steel (AISI52100) with different surface roughness. A mini traction machine and SRV tribometer were used to measure the COF under rolling–sliding and pure sliding conditions. Mn.P and PC/MoS 2 exhibited a significant antifriction effect. The COF of the coated samples were less affected by the change in slide-to-roll ratio than that of the uncoated samples. As the wear time was prolonged, the running performance of the Mn.P coating improved relative to that of PC/MoS 2. The effects of roughness, rolling speed and contact loads of coatings on wear mechanisms were discussed. Only one of the contact pairs treated with Mn.P coating showed improved tribological behaviour. • Two kinds of gear coating were prepared on AISI52100 steel. • Tribological properties of Mn 3 (PO 4) 2 and PC/MoS 2 coatings was studied. • Significant friction reduction observed in case of Steel–Mn.P, Steel–PC/MoS 2. • Low wear obtained for coating under mechanical pressure during sliding motion. [ABSTRACT FROM AUTHOR]