Myakzyum Kh. Salakhov

Electrochemical design of plasmonic nanoantennas for tip-enhanced optical spectroscopy and imaging performance

Optical nanoantennas play a crucial role in controlling near-fields on the nanoscale and being counterparts of commonly used conventional optical components such as lens, prisms, gratings, etc. for shaping the wavefront of light in the far-field. In this paper we highlight a dc-pulsed voltage electrochemical etching method with a self-tuneable duty cycle for highly reproducible design of plasmonic (metallic) nanoantennas. With the method, we introduce such concepts as design, optimization and figure-of-merit for evaluating fabrication efficiency. The ability of the nanoantennas to enhance and localize the optical fields beyond the diffraction limit is statistically studied with Rayleigh scattering from the tip apex and tip-enhanced Raman spectroscopy of a single walled carbon nanotubes bundle.

A new approach of recognition of ellipsoidal micro- and nanoparticles on AFM images and determination of their sizes

In this work we develop an approach of automatic recognition of ellipsoidal particles on the atomic force microscopy (AFM) image and determination of their size, which is based on image segmentation and the surface approximation by ellipsoids. In addition to the comparative simplicity and rapidity of processing, this method allows us to determine the size of particles, the surface of which is not completely visible on the image. The proposed method showed good results on simulated images including noisy ones. Using this algorithm the size distributions of silica particles on experimental AFM images have been determined.