invention relates to methods of creating devices which perform linear conversion of electromagnetic signals between a large number of channels. Invention can be used as an element of optical computing devices, when implementing separate elements of communication and computer networks serving a large number of subscribers and computing nodes; these elements and networks can be both classical and quantum. In addition, the invention can be used to design devices which perform analysis and synthesis of multimode electromagnetic fields. N- channel linear converter of electromagnetic signals includes N channels formed by N inputs and N outputs of a linear converter and M cascade-connected modules, where M ≥ N + 1, preferably M = 2N, each of which includes N module inputs, N module outputs and two- channel conversion units, providing conversion of signals from module inputs to module outputs and arranged in parallel inside module, and including one static divider comprising two divider inputs and two divider outputs, and one phase shift element located at one of the inputs or at one of the outputs of the static divider; inputs of the first module are inputs of the linear converter, outputs of the module M are outputs of the linear converter; wherein in case of odd N in each layer there is (Nl)/2 conversion units, as well as one free layer channel, which carries out signal from layer input to its corresponding output without conversion and located either before the first transformation unit, if in the adjacent layer it was located after the last conversion unit, or after the last conversion unit, if in the adjacent layer it is located before the first conversion unit; in case of even N, modules are characterized by alternating number of conversion units: module contains either N/2 conversion units if adjacent module contains (N/2)-1 conversion units, or in module contains (N/2)-1 conversion units, if adjacent module contains N/2 conversion units; wherein module containing (N/2)-l conversion units, also includes 2 free channels of module, performing signal transfer from module input to its corresponding output without conversion, one of which connects first input of module with first output of module, and other connects input and output of last module; where static dividers for conversion units are selected arbitrary with power transmission coefficient from 1/2 to 4/5, and phase shift elements are selected to implement a linear transformation given in advance using a certain transfer matrix.

Invention relates to the field of quantum cryptography. Technical result is achieved due to the fact that at the stage of transmission of the series of packages the length of the series of parcels is set and for each sending in the series the preparation of the transmitting and receiving sides is performed, transmission of the sending by the transmitting side and reception of the sending by the receiving side, wherein preparation of transmitting side includes selecting randomly and equitably one of two transmission side bases, selecting randomly and equitably one of two phase values in the selected basis, synchronizing the total time between the transmitting and receiving sides and preparing the transmitting side of the quantum state which unambiguously corresponds to the selected phase value.

Invention relates to the field of optics and quantum physics and relates to the educational and scientific laboratory bench for conducting studies of polarization and correlation properties of single-photon, biphoton, coherent and thermal light fields, Hong-Ou-Mandel interference and homodyne detection. Test bench includes a pumping laser module, a biphoton source module, polarization measurement modules in channels A and B, a correlation measurement module, a coherent and thermal state source module and a homodyne detection module. Biphoton source module includes a polarization controller and nonlinear crystals. Channels A and B contain polarization controllers of biphoton radiation, a polarization filter and/or a beam splitter. Correlation measurement module comprises single-photon detectors connected to a pulse correlator connected to a computer. Coherent and thermal state source module comprises a laser and a beam splitter which divides light into two channels, in one of which a matte disk is placed, which is intended for modulation of phase and amplitude laser radiation at random.

Invention relates to methods of creating devices which perform linear conversion of electromagnetic signals between a large number of channels. Invention is an N-channel linear converter of electromagnetic signals, where N>2, comprising N channels for signals and M signal mixing units, each of which includes N inputs and N outputs and is characterized by a transfer matrix with complex elements of modulus less than 1, wherein mixing units are connected in series, and at least one input and one output of at least one mixing unit comprises a phase shift element, wherein the mixing units are made with transfer matrices, for which the ratio of at least two corresponding elements of the transfer matrices of at least two mixing units is different from 1, and at the input of at least one mixing unit the number of phase shift elements does not exceed N-2 and the signal conversion method used by the converter.

Invention relates to optics, specifically to methods of creating linear optical devices which perform linear conversions between a large number of channels. Conversion of each step is realized in parallel by several modules whose dimensions are much smaller than the dimension of the general transformation. In a two-stage scheme, only one interconnect layer is required between modules.

Group of inventions relates to integrated optics, and in particular to methods for producing a balanced divider in circuits based on waveguides formed in the volume of a solid-state workpiece by pulsed laser radiation. Method of manufacturing a divider in an integrated optical scheme consists in forming in the dielectric preform a region of interaction between contiguous waveguides. To do this, use a billet of quartz and form a waveguide in its volume with a linear cross-sectional size d=1÷6 microns by focusing pulsed laser radiation with a frequency ƒ= 2÷4 MHz and the average power of a single pulse p= 50÷500 kW when moving the workpiece relative to the focus of the radiation with a speed of V=0.4÷0.8 mm/ sec. At the interaction site, the waveguides are brought closer to the distance of g=1÷2 microns.

Device includes a laser radiation source, a slit diaphragm, a beam expander, and a sample holder with a mirror mounted thereon. A laser with a tunable wavelength is used as the laser radiation source. The beam expander consists of the collecting and diffusing lenses. The cutting line of the slit diaphragm is parallel to the intersection line of the mirror planes and the sample holder.

Layer of resist is applied, which is chosen as a low-molecular-weight polystyrene, onto the substrate by the method of thermal vacuum deposition,whilethetemperatureofthesubstrateduring the deposition is not more than 30°C; a latent image is formed on the substrate by local exposure of a high-energy electron beam with a light dose of 2000-20000 mcC/cm²; a resist is developed, when the substrate is heated in a vacuum to the temperature of 600-800 K and at the pressure of not more than 10⁻¹ mbar and plasma etching to transfer the pattern of the resist mask to the substrate to form the micro- and nanostructure on the substrate.

Invention refers to optics, namely to a light intensity modulation method for optical and near infrared ranges. The invention can be used in the applied magneto-optics, optoelectronics, photonics, as well as sensor technology. The method for intensity modulation of transmitted or reflected electromagnetic radiation using a magnetoplasmonic crystal includes creation of a bidimensional magnetoplasmonic crystal consisting of a transparent dielectric substrate, a two- dimensional array of noble metal particles of subwave size immersed into the thin magnetic dielectric layer with a thickness not smaller than the particle size; lighting of magnetoplasmonic crystal by TM-polarized electromagnetic radiation upon application of a magnetic field in the geometry of the equatorial magneto-optical Kerr effect.

Invention relates to microelectronics technology, and can be used for producing functional elements of nanoelectronics. The method of manufacturing elements with nanostructures for local probe systems comprises application on the substrate of monocrystalline silicon with orientation {100} of at least one layer of masking coating, in which a template pattern is formed with determining of at least three regions disposed on mutually perpendicular axes coinciding with two perpendicular crystallographic axis <110> of the substrate, setting the direction of the substrate breaking to the corresponding number of elements and forming on the surface of the masking coating of each element near the intersection point of the said axes of the platform for placement of the nanostructure, liquid etching of the substrate through the template pattern formed in the masking coating till appearance of etching figures in the substrate body in the form of triangular grooves formed by the intersection of planes {111} of the substrate, the formation of nanostructures on the said platforms with lithographic methods and dividing the substrate to the said elements along the lines formed by the grooves.