Experimental observation of Dyakonov plasmons in the mid-infrared

AbstractIn this work, we report on observation of Dyakonov plasmons at an interface with a hyperbolic metamaterial in the mid-IR. The hyperbolic metamaterial is implemented as a CMOS-compatible high aspect ratio grating structure with aluminium-doped ZnO (AZO) ridges grown by atomic layer deposition in deep trench silicon matrix. The dispersion of Dyakonov plasmons is characterized by the attenuated total reflection method in the Otto configuration. We demonstrate that Dyakonov plasmons propagate in a broad range of directions (a few tens of degrees) in contrast to the classical Dyakonov surface waves (about one tenth of degree). The obtained results provide useful guidelines for practical implementations of structures supporting Dyakonov plasmons in the mid-IR. </jats:p

Affinity purification of ribosomes with a lethal G2655C mutation in 23 S rRNA that affects the translocation

A method for preparation of Escherichia coli ribosomes carrying lethal mutations in 23 S rRNA was developed. The method is based on the site-directed incorporation of a streptavidin binding tag into functionally neutral sites of the 23 S rRNA and subsequent affinity chromatography. It was tested with ribosomes mutated at the 23 S rRNA position 2655 (the elongation factor (EF)-G binding site). Ribosomes carrying the lethal G2655C mutation were purified and studied in vitro. It was found in particular that this mutation confers strong inhibition of the translocation process but only moderately affects GTPase activity and binding of EF-G