Leader: Vladimir Zhaketov
Work phone number: +7 (496) 216-28-75
Work E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Scientific problem:
A quasicrystal is a solid the structure of which is characterized by the long-range order but it is not periodic, that is, it is described by a symmetry forbidden in classical crystallography [1]. Moreover, quasicrystals, like ordinary crystals, are characterized by a discrete diffraction pattern. The geometric abstraction describing quasicrystals is the Penrose tiling. Currently, numerous materials that possess quasi-crystallinity, both artificially synthesized and natural, are widely known. It is noteworthy that it is possible to develop artificial layered systems that possess quasi-crystallinity in the direction perpendicular to the plane of the structure. The superconducting and magnetic properties of quasicrystals are intriguing. Paper [2] describes the observation of a superconducting transition in a bulk Al-Zn-Mg quasicrystal at a temperature Tc<0.05 K. Thus, the authors demonstrated the possibility of the occurrence of superconducting correlations in quasi-ordered systems and this type of superconductivity was called "fractal". Regarding about the magnetic behavior in a number of quasicrystals, a spin glass state has been observed but in [3] it was shown that "exotic" long-range magnetic order is possible in Au−Ga−Gd and Au−Ga−Tb quasicrystals. Moreover, the typical Curie temperatures for these materials are relatively low T_Curie<25 K. The described materials have complex chemical and electronic structures and for the investigation of superconducting and magnetic effects, simpler systems are preferable that are proposed to be investigated in this paper.
1. Vekilov Yu.Kh. et al. // Phys. Usp., Vol. 180, No. 6 (2010)
2. Kamiya K. et al. // Nature Communications, 9:154 (2018)
3. Ryuji Tamura et al. // J. Am. Chem. Soc. 2021, 143, 19938−19944"
Objective:
The aim of the project is to study the properties of magnetic ordering in quasi-periodic systems of the ferromagnet/superconductor type, combined systems of type 1 and type 2 superconductors, systems with interlayer magnetic exchange interaction and to compare the properties of these systems with the properties of similar superlattices.
Tasks:
1. Investigation of proximity effects in layered Fibonacci systems of the ferromagnet/superconductor type.
2. Investigation of vortex state pecularities in quasiperiodic heterosystems of the type I superconductor/type II superconductor.
3. Investigation of exchange interaction pecularities in quasiperiodic magnetic systems of the Fe/Cr type.
Research facilities: