arXiv subjects

Sergey I. Bozhko

Publications and source records attributed to Sergey I. Bozhko.

3 recordsLinked to original sources

arXiv2022

Local laser oxidation of titanium film for post-fabrication trimming of photonic integrated circuits

Local laser oxidation of a thin titanium film is considered as a means of a precise adjustment of losses and effective refractive index of dielectric optical waveguides. A fine phase control of an operating point and extinction ratio enhancement up to 57 dB were demonstrated using an integrated optical Ti:LiNbO3 Mach-Zehnder modulator. This technique only slightly affects the dielectric waveguide material and is very promising for a high precision permanent trimming of photonic devices based on dielectric waveguides of different material platforms and fabrication technologies.

physics.app-ph↗

arXiv2017

Step bunching with both directions of the current: Vicinal W(110) surfaces versus atomistic scale model

We report for the first time the observation of bunching of monoatomic steps on vicinal W(110) surfaces induced by step up or step down currents across the steps. Measurements reveal that the size scaling exponent γ, connecting the maximal slope of a bunch with its height, differs depending on the current direction. We provide a numerical perspective by using an atomistic scale model with a conserved surface flux to mimic experimental conditions, and also for the first time show that there is an interval of parameters in which the vicinal surface is unstable against step bunching for both directions of the adatom drift.

cond-mat.mtrl-sci↗

arXiv2016

Fabrication of sharp atomic force microscope probes using in-situ local electric field induced deposition under ambient conditions

We demonstrate a simple method to significantly improve the sharpness of standard silicon probes for an atomic force microscope, or to repair a damaged probe. The method is based on creating and maintaining a strong, spatially localized electric field in the air gap between the probe tip and the surface of conductive sample. Under these conditions, nanostructure growth takes place on both the sample and the tip. The most likely mechanism is the decomposition of atmospheric adsorbate with subsequent deposition of carbon structures. This makes it possible to grow a spike of a few hundred nanometers in length on the tip. We further demonstrate that probes obtained by this method can be used for high-resolution scanning. It is important to note that all process operations are carried out in-situ, in air and do not require the use of closed chambers or any additional equipment beyond the atomic force microscope itself.

cond-mat.mes-hall↗