A high-amplitude microwave magnetic field localized at the nanoscale is a desirable tool for various applications within the rapidly developing field of nanomagnetism. Here, we drive magnetization precession by coherent phonons in a metal ferromagnetic nanograting and generate ac-magnetic induction with extremely high amplitude (up to 10 mT) and nanometer scale localization in the grating grooves. We trigger the magnetization by a laser pulse which excites localized surface acoustic waves. The developed technique has prospective uses in several areas of research and technology, including spatially resolved access to spin states for quantum technologies.The exploration of magnetism at the nanoscale continues to be a rapidly developing field. Magnetic recording with ultrahigh densities [1] for data storage, magnetic resonant imaging with nanometer resolution [2, 3] for medicine and biology, addressing the magnetic states of atoms [4][5][6][7][8] for quantum computing, and ultrasensitive magnetic sensing [9] are the most prominent examples within the multifaceted research field of nanomagnetism. Most of the proposed concepts and prototypes utilize oscillating (ac-) magnetic fields with frequencies from millions up to hundreds of billions of cycles per second (10 6 -10 11 Hz). The oscillating magnetic fields are used to override the coercivity of ferromagnetic grains [10], to set atomic magnetic moments to a desired state [2,3,9], and to encode quantum information into spin states [4][5][6][7][8]11]. These examples utilize conventional methods for the generation of ac-magnetic fields: an external rf-generator in combination with a microwire [2][3][4][5][9][10][11] or a microwave cavity [6][7][8]11]. This methodology cannot be applied at the nanometer scale. A key breakthrough would be nanoscale generation of high-amplitude, monochromatic ac-magnetic fields. This would open the possibility to address neighboring nano-objects, e.g. spin qubits, independently, and to reduce the energy consumption in magnetic devices. It is however a challenging task to reach this goal because current technologies do not allow one to control the frequency, bandwidth and amplitude of an ac-magnetic field on the nanoscale.An efficient way to generate a high-frequency ac magnetic field is to induce coherent magnetization precession in a ferromagnet. The magnetization of ferromagnetic metals may be as large as 2 T. Precessional motion with frequencies of 10 GHz allows the generation of highamplitude microwave magnetic fields on the picosecond time scale. The magnetization precession can be driven by dc-spin polarized currents [12]. This approach is realized in microwave generators based on spin torque nanooscillators, but has severe limitations, e.g. in combining large amplitudes and high frequencies [13]. Coherent phonons, bulk [14,15] or surface [16,17] acoustic waves, have been successfully used for exciting the magnetization precession in ferromagnetic films. The effect of a surface acoustic wave (SAW) on the magnetic order in a ferromag...

Using Rutherford backscattering spectroscopy, nuclear elastic resonance analysis, atomic force microscopy, transmission electron microscopy, and wear resistance and microhardness tests, the alloy Ti41–V41–Al18 was investigated after Fe ion (60 kV) and Zr (40 kV) ion implantation and subsequent high-current electron beam (HCEB) irradiation at an energy flow density of 6 J/cm2, called duplex treatment. Profiles show that the maximum concentration of Fe ions was 16.5 at. % at 85 nm from sample surface and that of Zr ions was 0.85 at. % at 56 nm. The maximum of the Fe concentration profile was found to shift to the large sample depth toward after increasing the implantation dose. The surface alloy layer is composed of a number of structures: grains of dislocation substructure (2×1010 cm−2), grains with plates, and grains with packed martensite. The disorientation of regions is observed. After HCEB treatment, the disorientation of microregions increases (Δα=7.5°) and particles of Ti2Fe are formed. After double implantation, the dry friction wear and the friction coefficient decreased. After the duplex treatment, the thickness of the hardened layer and the wear resistance increased.

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Carboxylic acids prepared from hexafluoropropene oxide CF 3 CF 2 CF 2 O[CF(CF 3 )CF 2 O] n CF .(CF 3 )COOH [n = 0, 2,5-bis(trifluoromethyl)-3,6-dioxaperfluorononanoic acid; n = 1, 2,5,8-tris(trifluoromethyl)-3,6,9-trioxaperfluorododecanoic acid], according to voltammetric data, enter the Kolbe reaction both at the Pt anode and at anodes from carbon materials in H 2 O3CH 3 CN and CH 3 OH3CH 3 CN solutions. The critical potential appreciably depends both on the anode material and on the solvent composition. Favorable effect of pyridine additions in H 2 O3CH 3 CN solutions is due to replacement of water molecules from the electrical double layer. The sodium ions exert a negative effect on the Kolbe synthesis.Anodic oxidation of solutions of aliphatic carboxylic acids in water or organic solvents involves decarboxylation of the acid accompanied by dimerization of the aliphatic residue:This reaction is known as the Kolbe synthesis. In electrolysis of a mixture of two acids RCOOH and R`COOH, the cross dimer R3R`can form along with the symmetrical hydrocarbons. Oxa acids prepared from oligomers of tetrafluoroethene and hexafluoropropene oxides form both symmetrical and cross Kolbe dimers in reasonable yields [133]. The acid molecules prepared from hexafluoropropene oxide oligomers contain side trifluoromethyl groups exhibiting a strong inductive effect. These groups neutralize the capability of the oxa group for specific interaction with the anode surface, which favors concentration of the acid molecules at the anode3electrolyte phase boundary. Such absorption layers are formed relatively readily, and in the electrochemical properties the acids derived from hexafluoropropene oxide resemble trifluoroacetic acid to a greater extent than do the previously studied acids derived from tetrafluoroethene oxide, [CF 3 O(CF 2 CF 2 O) n CF 2 COOH, n = 33 4] [2].To elucidate specific features of the mechanism of the Kolbe electrosynthesis with fluorocarboxylic acids derived from hexafluoropropene oxide, we studied how the anode material (platinum, glassy carbon, pyrographite, carbon3carbon composite), solvent, and pyridine additions affect the voltammetric characteristucs of the acids CF 3 CF 2 CF 2 O[CF(CF 3 )CF 2 O] n CF . (CF 3 )COOH [n = 0, 2,5-bis(trifluoromethyl)-3,6-dioxaperfluorononanoic acid I; n = 1, 2,5,8-tris(trifluoromethyl)-3,6,9-trioxaperfluorododecanoic acid II]. Acids I and II under definite conditions (mainly in nonaqueous media with Pt or glassy carbon anodes) give voltammetric curves characteristic of the occurrence of the Kolbe synthesis. The semilog plots have two linear portions. The first portion starts at 1.13 1.4 V depending on the experimental conditions and corresponds to the oxidation of the carboxylic acid molecules. Then, after reaching the so-called critical potential, the electrical double layer undergoes rearrangement, and the second Tafel portion starts (potential range 2.0 32.4 V), within which the Kolbe anodic condensation occurs.The best defined curves were obtained in an anhydrous acetonitrile...

CO2‐laser produced damping of electron‐hole drop (EHD) luminescence in Ge at laser intensities of 104 to 5 × 106 W/cm2 is reported. The observed effect is explained to be due to heating of the EHD by 10.6 μm radiation and driving of e‐h plasma by phonon wind generated during absorption and relaxation of hot nonequilibrium carriers.