Solvatochromic probes for detecting hydrogen-bond-donating solvents

Hydrogen bonding heavily influences conformations, rate of reactions, and chemical equilibria. The development of a method to monitor hydrogen bonding interactions independent of polarity is challenging as both are linked. We have developed two solvatochromic dyes that detect hydrogen-bond-donating solvents. The unique solvatochromism of the triazine architecture has allowed the development of probes that monitor hydrogen-bond-donating species including water

Microanalysis of magnetic structure of yttrium-iron garnet films by using the scanning probe microscopy methods

In this paper, the features of the microstructure of magnetic domains observed in ferrite-garnet films (FGF) have been presented. The studied FGF with orientation (111) were grown on gallium-gadolinium substrate by using liquid-phase epitaxy. The study of distribution inherent to magnetic domains was carried out using magnetic force microscopy (MFM) with the scanning probe microscope NanoScope IIIa Dimension 3000TM. In the course of these researches, optimization of the MFM method was carried out to obtain high-quality and correct images of magnetic domains in FGF. Nanorelief and magnetic microstructure of FGF surface were studied, depending on their thickness, on external magnetic field and doses of boron ion implantation. For these objects, it was established that stripe domain structure is characteristic, the period of which depends on the film thickness. The nature of transformation of domain structure depending on thickness is close to that theoretically predictable at low thicknesses (up to 10 µm). Nanorelief of film surfaces is virtually unchanged depending on thickness. An external magnetic field with the magnitude 4 mT causes significant changes in domain configuration and allows to visualize heterogeneity of magnetic structure. Ion implantation leads to a slight smoothing of nanorelief films (roughness of 0.2 nm) and to more accurate displaying the magnetic microstructure, which is associated with processes of structural ordering under ionic bombardment

Integrated room temperature single-photon source for quantum key distribution.

High-purity single-photon sources (SPS) that can operate at room temperature are highly desirable for a myriad of applications, including quantum photonics and quantum key distribution. In this work, we realize an ultra-bright solid-state SPS based on an atomic defect in hexagonal boron nitride (hBN) integrated with a solid immersion lens (SIL). The SIL increases the source efficiency by a factor of six, and the integrated system is capable of producing over ten million single photons per second at room temperature. Our results are promising for practical applications of SPS in quantum communication protocols