Laboratory for Topological Quantum Phenomena in Superconductive Systems

Scientific results:

1. One of the most important achievements of the team over the period starting on January 1. 2018 was a series of pioneering research efforts of the electronic and magnetic properties of new materials and devices — ferromagnetic superconductors, low-dimensional crystals of topological insulators, magnetic insulators, magnetic topological insulators, superconductor/ferromagnetic and superconductor/topological insulator systems on the basis of thin films, exfoliated and PVD-synthesized nanocrystals, as well as segmented nanowires. It is worth noting that to research the electron properties low-dimensional structures we developed and refined technological and research methodologies that are unique at the world level and allow to implement hybrid devices that can be used in cryoelectronics. 
2. Our researchers have predicted and experimentally demonstrated the existence of the first antiferromagnetic topological insulators.
3. We have found a new superconducting Meissner and vortex phase, found spontaneous generation of a pair of quantum vortices in so-called  magnetic semiconductors.
4. For the first time we have demonstrated the evolution of a quantum vortex induced in a non-superconducting material.
5. We have visualized the dynamics of vortices of superconducting currents carrying a magnetic flow quant in long Josephson contacts. On the basis of the research we proposed a method for implementing a sensitive magnetic field detector, an ultra-low-dissipation method of implementing memory and a logical device.
6. Our researchers have developed a methodology for researching ultra-thin films under conditions of ultra-high vacuum immediately after spraying.
7. We have researched superconducting states in thin-layer hybrid superconducting/ferromagnetic bilayers. We thoroughly studied the structure of triplet correlations in such systems. Our researchers have built microscopic theory of magnetoelectric effects.
8. The Laboratory has studied the feasibility of using magnetoelectric effects in low-dissipation spintronics, in particular, the possibility of monitoring magnetic defects and controlling them using a superconducting condensate. We predicted and described composite quasiparticles of the magnon-triplet Cooper pairs.
9. We have conducted a theoretical research of the magnetoelectric effect in Josephson contacts through a ferromagnetic and antiferromagnetic. This effect plays an exceptionally important role in low-dissipation spintronics, since it ensures a direct link between the magnetization of a magnetic and the phase of a superconducting condensate.  For the first time we have studied a fundamentally new type of the state of a Josephson system – a resistive state in the presence of a magnetization dynamic.
10. We have demonstrated good prospects of using magnetoelectric effects in spintronics: magnetization control, the possibility of creating cryogenic memory, controlling magnetic anisotropy, the electrical detection of magnetization flipping and the detailed electric detection of the magnetic dynamics, a new physical principle of long-distance magnetic interaction through the condensate phase.
11. We have researched the potential of using superconductor/magnetic heterostructures  in  spin caloritronics. Our research demonstrates that in thin-film superconductor/(anti)ferromagnetic hybrid structures it is possible to achieve a multi-fold increase in the efficiency of thermally-induced motion of magnetic defects, which makes superconducting hybrids the main paradigm in spin caloritronics.
12. The Laboratory has predicted the generation of triplet ultraconducting correlations controlled by the motion of superconducting condensate. The correlations are the base elements for superconducting electronics. Relying on this effect, we proposed a concept of a Josephson transistor, a controlled pi-shifter and a photomagnetic element.
13. Our researchers have experimentally observed the state of a Mott insulator.
14. We have studied the interaction of the superconducting and the ferromagnetic order parameter in the iron-containing high-temperature superconductor EuRbFe₄As4.

Implemented results of research:

We are conducting intense work with the industrial institute of Rosatom, the N. L. Dukhov All-Russian Research Institute of Automation, to which end we have launched the base department «Department of the Basic and Applied Physics of Micro- and Nanostructures» relying on the Laboratory. We are collaborating with other teams to develop cryogenic electronics, in particular, high-frequency cryogenic generators on a chip, circulators based on magnetic topological insulators, sensors and other quantum, digital and neuromorphic devices. 

Education and career development:

• 4 Candidate of Sciences dissertations, 8 master’s degree theses, 7 bachelor’s degree theses have been prepared and defended.

• At our Laboratory much attention is paid to training young processionals and engaging them in scientific research. By working on cutting-edge and complex problems of superconductors, undergraduate and postgraduate students, young researchers  conduct  research in a modern well-equipped laboratory at the Moscow Institute of Physics and Technology under the supervision of leading scientists who posses extensive academic experience.
• In 2018–2022 employees of the Laboratory participated in organizing and staging international academic events in the Laboratory’s area of studies in Moscow. In July 2016, we conducted a school for young researchers in the village of Listvyanka (Lake Baikal) with the topic «Physics of semiconductor hybrid structures». From July 31 to August 3, 2018 employees of the Laboratory collaborated with colleagues from the National University of Science and Technology MISiS and the Russian Quantum Center to stage the first conference on modern superconductor quantum technologies in Moscow. On August 22–27, 2022 as part of the 8^th Eurasian Symposium «Trends in Mathematics in Kazan, in collaboration with the National University of Science and Technology MISIS we conducted the 2^nd International School «Superconductor technologies for quantum information processing» Superconducting Quantum Hardware.
• We are conducting continuous work with students. More than 20 students have performed their research work at the Laboratory over the report period. A methodological manual on working with a tunnel scanning microscope has been developed, as well as a methodological manual on the automated of physical experiments.  

Organizational and structural changes:

• Over the course of the existence of the Laboratory, we have organized a full-cycle infrastructure that allows to synthesize, produce and research object. The infrastructure features electron lithography on the basis of the Center for the Collective Use of Scientific Equipment of the Moscow Institute of Physics and Technology, thin-film spraying by magnetron and electron-beam sputtering, scanning tunnel microscopy/spectroscopy at a temperature of 1 К and in a magnetic field of up to 3 Т, magnetic force microscopy at a temperature of 4 К and in a magnetic field of up to 9 Т, ultra-low-temperature (10 mK) static (dc) and radio-frequency (rf) research in a solution refrigerator in magnetic fields of up to10 T. 
• We have created an infrastructure for liquid helium recirculation. 
• Our researchers have conducted comprehensive work to implement methodologies         devices for conducting high-precision cryogenic research. 
• The Laboratory is developing quantum superconducting elements for the implementation of " semiconductor computing devices. 
• Employees of the Laboratory have developed and experimentally tested a methodology for the use of superconducting qubit circuits for quantum metrology problems: ultra-high-precision measurement of magnetic fields, the non-invasive measurement of local temperature in qubit chips. 
• We have developed a number of unique quantum metrology algorithms based on a quantum algorithm of phase assessment and machine learning methods.
• In 2021, by decision of the Rector and on the initiative of Nobel Prize winner Sir Andrei Geim the Laboratory became the basis of a new research center for advanced methods of mesophysics and nanotechnology of the Moscow Institute of Physics and Technology. Lead research fellow of the Laboratory, Candidate of Sciences in Physics and Mathematics Vasiliy Stolyarov became the chair of the created center.

Collaborations:

• University of Twente, the Netherlands: joint research, student exchanges.
• Forschungszentrum Jülich, Germany: joint research.
• Sorbonne University, Paris, France: joint research , student exchanges.
• Donostia International Physics Center, San Sebastian, Spain: joint research.
• N. L. Dukhov All-Russian Research Institute of Automation, Moscow, Russia: joint research, student exchanges.
• National University of Science and Technology MISIS, Moscow, Russia: joint research, student exchanges.
• Institute of Solid State Physics of the Russian Academy of Sciences, Chernogolovka, Moscow Region, Russia: joint research.
• Kazan Federal University, Kazan, Russia: joint research, student exchanges.