Laboratory building, room 122
Moscow Institute of Physics and Technology
Dolgoprudny, Russia
contact email address: nanotheory@phystech.edu (head M.V.Feigel'man, deputy head I.V.Zagorodnev)
Research topics


Seminar na Fizfake MGU, Tuesday, April 17, 2018, Fizfak MGU, aud. 332b, 5:00 pm Tuğrul Hakioğlu (Department of Physics and Energy Institute, İstanbul Technical University, Turkey) Understanding the Skyrmion Anomalies in Strong Topological Insulators: An Interaction Approach Interactions between the surface and the bulk in a topological insulator (TI) cause a finite quasiparticle lifetime of the topological surface states (TSS) as shown by the recent experiments for Bi2X3 (X=Se,Te). Previously, hexagonally warped topological band has been detected and other anomalies related to warping have been reported. The most remarkable among which is the 6fold periodic spin canting anomaly (SCA) of the inplane spin around the spin1/2 vortex. This talk is focused on understanding this SCA from an interaction point of view between the TSS and the bulk. We first device a general scheme based on interactions and the spinoffdiagonal component of the self energy. It is shown that, the spinoff diagonal interaction channel is topology preserving. Then the effective interaction strength, strong spinorbit coupling and the Fermi surface warping is shown to cooperate in giving rise to the periodic spin canting anomaly. Our result points at the presence of the topology friendly interaction channels in strong TIs. KAK POPAST' NA SEMINAR: Na fizfake MGU propusknoi rezhim, zhelatel'no imet' s soboi pasport. Organizatory vstretyat uchastnikov. Telefon organizatora: +79117032266 (Mikhail Evgen'evich Zhuravlev). 
Scientific Council of the Landau Institute, Friday, April 13, 2018, Landau Institute, 11:30 am Pavel Grigor'ev Magnetic oscillations of inplane conductivity in quasitwodimensional metals We develop the theory of transverse magnetoresistance in layered quasitwodimensional metals. Using the Kubo formula and harmonic expansion we calculate intralayer conductivity in a magnetic field perpendicular to conducting layers. The analytical expressions for the amplitudes and phases of magnetic quantum oscillations (MQO) and of the socalled slow oscillations (SlO) are derived and applied to analyze their behavior as a function of several parameters: magnetic field strength, interlayer transfer integral and the Landaulevel width. Both the MQO and SlO of intralayer and interlayer conductivity have approximately opposite phase in weak magnetic field and the same phase in strong field. The amplitude of SlO of intralayer conductivity changes sign at $\omega_c\tau\approx\sqrt{3}$. There are several other qualitative differences between magnetic oscillations of inplane and outofplane conductivity. The results obtained are useful to analyze experimental data on magnetoresistance oscillations in various strongly anisotropic quasi2D metals. 