Scientific results:
- We have studied the effects of the generation of the third optical harmonic in produced samples of individual nanoparticles of indirect band gap semiconductors by means of nonlinear optical measurements in the case of both Gaussian and cylindrical vector beams of pumping laser radiation. It has been experimentally demonstrated that the amplification of nonlinear-optical signal is observed in the magnetic quadrupole resonance of a single particle during its excitation by a azimuthally-polarized vector beam of pumping radiation in an electric quadruple resonance in the case of a radially-polarized vector beam. We obtained images of an inverse Fourier plane using polarimetry of Stokes parameters to determine the structure of the distribution of polarization and intensity of the radiation of the third optical harmonic in a single subwave nano-object.
- We have obtained temporal dependencies of the modulation of the refractive index when measuring the integral signal from the probe (with a monochromator) for a photon-crystal structure and for a gold film on glass. It has been found that excitation of Tamm plasmon-polaritons leads to am amplification of modulation of the reflective index by 17 times compared to a pure gold film.
- Our researchers have computed the Purcell factor and the power of saturation of the luminescence of SiV coloring centers depending on the size of diamond nanoparticles. It has been shown that Mie resonance in submicron diamond nanoparticles leads to a several-fold change in the rate of radiative transitions of coloring centers, which corresponds to the variation of the lifetime of a particle by several per cent. The dependence of the power of saturation during continuous laser pumping on the size of the particle is non-monotonous, which is caused by excitation of resonances both at the frequency of pumping and at the frequency of luminescence. The expected dispersion of the power of saturation for diamond particles with sizes ranging from 200 to 400 nm is more than five-fold.
- We have developed, produced and experimentally researched a high-Q-factor metasurface made of amorphous germanium, which demonstrates photo-induced transformation of frequency due to parameters of mega-atoms changing during the pulse. Using pump-probing, we found a change of the spectral features of the probing beam and its third optical harmonic at negative delay times. We demonstrated a shift to the short-wave region by 10 nm and a 40 per cent broadening of the spectrum at ultra-short times, practically complete suppression of the third harmonic at positive delays.
- We have developed a concept of a micro-dimensional Otto scheme for a normal angle of incidence using polymer microprisms printed on the surface of photonic crystals using two-photon lithography that have a submicron gap between the base and the surface of the photonic crystal. We found the possibility of focusing Bloch surface waves at the same time with their excitation using prisms with inclined faces in the shape of cone sectors.
- The Laboratory has experimentally detected directed excitation of Bloch surface waves using nano- and micro-lasers, which are crystalline nano- and microdimensional wires, as well as micro-plates of halide perovskites CsPbBr3 placed on the surface of a one-dimensional photonic crystal.
- A new method has been implemented for training an artificial neural network for the problem of selecting the parameters of multi-layer photonic structures from a specified angular spectrum of the refractive index, which consists of a combination of a neutral network with propagation matrix method. We demonstrated the possibility of using the trained neural network to develop an analog optical differentiator.
Implemented results of research:
The Laboratory has obtained a number of patents for inventions based on the experiments conducted within our project.
Education and career development:
8 Candidate of Science dissertations have been prepared and defended.
Internships of employees of the Laboratory at KU Leuven (Belgium), the University of Brescia (Italy), Leibniz University Hannover (Germany).
In collaboration with ITMO University we organized the online summer schools in nanophotonics SLALOM: «School on Advanced Light-Emitting and Optical Materials» from 29 to 30 June 2020.
Organizational and infrastructural transformations:
Part of the equipment of the Laboratory and its rooms are part of the Center for the Collective Use of Scientific Equipment of Moscow State University «Technologies of Producing New Nanostructured Materials and Their Comprehensive Study».
Collaborations:
- KU Leuven (Belgium), University of Brescia (Italy), Friedrich Schiller University Jena (Germany), Australian National University (Australia): joint research, internships of employees of the Laboratory, joint publications.
- Bangor University (United Kingdom), Sandia National Laboratories (United States), University of Technology Sydney (Australia): joint research and publications.
- Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow Institute of Physics and Technology, Skolkovo Institute of Science and Technology: joint research and publications.
- ITMO University: joint research, organizing joint academic conferences and summer schools, joint publications.
- Immanuel Kant Baltic Federal University: joint research, internships of members of the academic team of the Laboratory, joint publications.
