This article presents a new simple method of creating light-absorbing carbon material for optical devices such as bolometers. A simple method of laser microstructuring of graphene oxide is used in order to create such material. The absorption values of more than 98% in the visible and more than 90% in the infrared range are achieved. Moreover thermal properties of the films, such as temperature dependence and the thermal response of the samples, are studied. The change in resistance with temperature is 13 Ohm K, temperature coefficient of resistance (TCR) is 0.3% K, and the sensitivity is 0.17 V W at 300 K. Thermal conductivity is rather high at ∼104 W m K at 300 K. The designed bolometer operates at room temperature using incandescent lamp as a light source. This technique suggests a new inexpensive way to create a selective absorption coating and/or active layer for optical devices. Developed GO and rGO films have a large surface area and high conductivity. These properties make carbon coatings a perfect candidate for creating a new type of optoelectronic devices (gas sensors, detectors of biological objects, etc.).

Ultra-thin magnetic dielectric films are of prime importance due to their applications for nanophotonics and spintronics. Here we propose an efficient method for the magneto-optical investigation of ultra-thin magnetic films that allows one to access their state of magnetization and magneto-optical properties. It is based on the surface-plasmon-polariton-assisted transverse magneto-optical Kerr effect (TMOKE). In our experiments sub-100nm-thick bismuth-substituted lutetium iron-garnet films covered with a plasmonic gold grating have been analyzed. The excitation of surface plasmon-polaritons provides resonance enhancement of TMOKE up to 0.04 and makes it easily detectable in experiment. For films thicker than 40 nm the TMOKE marginally depends on the film thickness. Further decrease of the film thickness diminishes TMOKE since for such thicknesses the surface plasmon-polariton field partly penetrates inside the nonmagnetic substrate. Nevertheless, the TMOKE remains measurable even for few-nm-thick films, which makes this technique unique for the magneto-optical study of ultra-thin films. Particularly, the proposed method reveals that the off-diagonal components of the magnetic film permittivity tensor grow slightly with the reduction of the film thickness.Currently, ultra-thin ferrimagnetic dielectric films are of significant interest due to their applications in nanophotonics, magnonics and spintronics [1][2][3][4][5][6]. Magnetic dielectrics like bismuthsubstituted iron-garnets have outstanding optical properties in the near infrared where they evince low optical absorption and a relatively large magneto-optical response [7][8][9][10]. Practical use of spintronic devices for magnetic information recording requires magnetic field confinement in the

Magnetometry and visualization of very small magnetic fields are vital for a large variety of the areas ranging from magnetocardiography and encephalography to nondistractive defectoscopy and ultra-low-frequency communications. It is very advantageous to measure magnetic fields using exchange-coupled spins in magnetically ordered media (flux-gate magnetometry).Here we introduce and demonstrate a novel concept of a roomtemperature magnetoplasmonic magnetic field sensor with high sensitivity and spatial resolution. It is based on the advanced fluxgate technique in which magnetization of the fully saturated magnetic film is rotated in the film plane and the monitored magnetic field is measured by detecting variation of transmittance through the sensing element: a magnetoplasmonic crystal. The experimental study revealed that such an approach allows one to reach the nT sensitivity level, which was limited by the noise of the laser. Moreover, we propose an approach to improve the sensitivity up to fT/Hz 1/2 and reach micrometer spatial resolution. Therefore, the demonstrated magnetoplasmonic magnetometry method is promising for mapping and visualization of ultrasmall magnetic fields.

The present paper is focused on an experimental study of the damage-to-failure mechanism of additively manufactured 316L stainless steel specimens subjected to very high cycle fatigue (VHCF) loading. Ultrasonic axial tension-compression tests were carried out on specimens for up to 109 cycles, and fracture surface analysis was performed. A fine granular area (FGA) surrounding internal defects was observed and formed a “fish-eye” fracture type. Nonmetallic inclusions and the lack of fusion within the fracture surfaces that were observed with SEM were assumed to be sources of damage initiation and growth of the FGAs. The characteristic diameter of the FGAs was ≈500 μm on the fracture surface and were induced by nonmetallic inclusions; this characteristic diameter was the same as that for the fracture surface induced by a lack of fusion. Fracture surfaces corresponding to the high cycle fatigue (HCF) regime were discussed as well to emphasize damage features related to the VHCF regime.

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