Oleg Tereshchenko

Institute of Semiconductor Physics, Novosibirsk State University · Physics department

It is known that Mn(Bi 1 – x Sb x ) 2 Te 4 is an intrinsic magnetic topological insulator, where the Dirac point can be localized at the Fermi level by substituting Bi atoms for Sb atoms to implement the quantum anomalous Hall effect and other unique quantum effects. It has already been shown that Mn(Bi 1 – x Sb x ) 2 Te 4 samples has antiferromagn...

Improving the efficiency of spin generation, injection, and detection remains a key challenge for semiconductor spintronics. Electrical injection and optical orientation are two methods of creating spin polarization in semiconductors, which traditionally require specially tailored p-n junctions, tunnel or Schottky barriers. Alternatively, we introd...

Correction for ‘Depth-resolved oxidational studies of Be/Al periodic multilayers investigated by X-ray photoelectron spectroscopy’ by Niranjan Kumar et al. , Phys. Chem. Chem. Phys. , 2023, 25 , 1205–1213, https://doi.org/10.1039/D2CP04778K.

We study ultrafast population dynamics in the topological surface state of Sb$_2$Te$_3$ in two-dimensional momentum space with time- and angle-resolved two-photon photoemission. Linear polarized mid-infrared pump pulses are used to permit a direct optical excitation across the Dirac point. We show that this resonant excitation is strongly enhanced...

The quantification of surface and subsurface oxidation of Be/Al periodic multilayer mirrors due to exposure in the ambient atmosphere was investigated by depth-resolved X-ray photoelectron spectroscopy. The contribution of oxidation was lower for the thicker layer of Al in the periodic structures since the surface was less chemically reactive for t...

An Erratum to this paper has been published: https://doi.org/10.1134/S0021364022340057

We study the electronic structure of the ferromagnetic spinel $\mathrm{Hg}\mathrm{Cr}_2\mathrm{Se}_4$ by soft-x-ray angle-resolved photoemission spectroscopy (SX-ARPES) and first-principles calculations. While a theoretical study has predicted that this material is a magnetic Weyl semimetal, SX-ARPES measurements give direct evidence for a semicond...

Magnetic topological insulators (MTIs) have recently become a subject of poignant interest; among them, Z2 topological insulators with magnetic moment ordering caused by embedded magnetic atoms attract special attention. In such systems, the case of magnetic anisotropy perpendicular to the surface that holds a topologically nontrivial surface state...

Intrinsic magnetic topological insulators (MTIs), such as an MnBi2Te4 family, have proved to be an essential platform for the study of various quantum effects and can be used for a range of applications from information storage and dissipationless spin and charge transfer to quantum computers. The latter requires the creation of Majorana fermions,...

New spin-dependent photoemission properties of alkali antimonide semiconductor cathodes are predicted based on the detected optical spin orientation effect and DFT band structure calculations. Using these results, the Na2KSb/Cs3Sb heterostructure is designed as a spin-polarized electron source in combination with the Al0.11Ga0.89As target as a spin...

We investigate the HfO 2 /Hg 0.78 Cd 0.22 Te interface fabricated by plasma-enhanced atomic layer deposition (PEALD) at 120 °C During the deposition of HfO 2 , no donor-like defects are introduced into mercury cadmium telluride. X-ray photoelectron spectroscopy and ellipsometry were used to establish the optimal process regime at 120 °C and to demo...

Recently discovered intrinsic magnetic topological insulators (IMTIs) constitute a unique class of quantum materials that combine magnetism and nontrivial topology. One of the most promising applications of these materials is Majorana fermion creation; Majorana fermions are expected to arise when a superconductor is in contact with the surface of a...

Microstructural properties of the beryllium (Be) and silicon (Si) in periodic multilayer mirrors Be/Si with the variation of film thickness were comprehensively determined by Raman scattering. For the thinner films, the structure of Be evolved in the amorphous phase, and it was transformed into the polycrystalline phase for thicker films. The Si fi...

New spin-dependent photoemission properties of alkali antimonide semiconductor cathodes are predicted based on the detected optical spin orientation effect and DFT band structure calculations. Using these results, the Na$_2$KSb/Cs$_3$Sb heterostructure is designed as a spin-polarized electron source in combination with the Al$_{0.11}$Ga$_{0.89}$As...

Contemporary studies of magnetic topological insulators (TIs) aimed at investigating Dirac point (DP) gaps by angle-resolved photoemission spectroscopy (ARPES) require ultrahigh energy, momentum, and spatial resolution. Despite satisfying all these conditions, accurate measurements can be spoiled by the well-known, but often neglected, effect of th...

Intrinsic magnetic topological insulator MnBi 2 Te 4 provides a promising platform to implement the quantum anomalous Hall effect at increased temperatures and other unique topological effects. However, to do this, the energy gap opening at the Dirac point should be located at the Fermi level. One of the widely used methods to shift the Dirac point...

Results on the creation and properties of transistor-type MIS structures (MIST) with an Al 2 O 3 thin-film gate dielectric based on PbSnTe : In films obtained by molecular beam epitaxy are presented. The source-drain current-voltage characteristics (CVC) and gate-controlled characteristics of the MIST at [BT=4.2 K have been investigated. It is show...

We selectively explore bulk-versus-surface high-harmonic generation in a topological insulator by tuning the driving frequency. Ballistic acceleration of Dirac currents manifests in continuously tunable non-integer harmonic orders and unique polarization fingerprints of the topological invariant.

We have optimized the growth conditions of the buffer layer for further deposition of Pb 1-x Sn x Te (x≥0.4), which has the properties of a crystalline topological insulator. To this end, a three-component heterostructure consisting of CaF 2 , BaF 2 , and Pb 0.7 Sn 0.3 Te : In layers was formed and optimized on the Si(111) surface. The surface morp...

Introducing magnetic exchange interaction into topological insulators is known to break the time-reversal symmetry and to open a gap at the Dirac point in the otherwise gapless topological surface states. This allows various novel topological quantum phenomena to be attained, including the quantum anomalous Hall effect and can lead to the emergence...

Polar Rashba-type semiconductor BiTeI doped with magnetic elements constitutes one of the most promising platforms for the future development of spintronics and quantum computing thanks to the combination of strong spin-orbit coupling and internal ferromagnetic ordering. The latter originates from magnetic impurities and is able to open an energy g...

We present temperature and laser-power dependent photoluminescence (PL) study of methylammonium lead iodide (CH3NH3PbI3) single crystals in the orthorhombic phase. At temperatures below 140 K, we revealed the multi-component PL emission. In addition to a free exciton with an energy of 1.65 eV, we found emission bands with peaks approximately equal...

The possibility of epitaxial growth of Pb 0.7 Sn 0.3 Te crystalline topological insulator films on the Si(111) surface was shown and epitaxial relations were found. It was shown that, depending on the growth temperature, it is possible to control not only the character of the morphology, but also, to a significant extent, the smoothness of the epit...

Recently discovered intrinsic antiferromagnetic topological insulator MnBi2Te4 presents an exciting platform for realization of the quantum anomalous Hall effect and a number of related phenomena at elevated temperatures. An important characteristic making this material attractive for applications is its predicted large magnetic gap at the Dirac po...

Nonreciprocal transport, where the left-to-right-flowing current differs from the right-to-left-flowing one, is an unexpected phenomenon in bulk crystals. BiTeBr is a noncentrosymmetric material, with a giant Rashba spin-orbit coupling which presents this unusual effect when placed in an in-plane magnetic field. It has been shown that this effect d...

Successful applications of a topological insulator (TI) in spintronics require its bandgap to be wider then in a typical TI and the energy position of the Dirac point in the dispersion relations to be away from the valence and conduction bands. In this study we grew Bi1.1Sb0.9Te2S crystals and examined their elemental composition, structural, optic...

Magneto-transport properties were studied on thin films of a 3D topological insulator (TI) Bi2Se3 grown on graphene (Gr) by physical vapor deposition. It was shown that the main contribution to the conductance is from the bulk states, whereas magnetoresistance is determined by both surface and bulk channels. The input of the charge transport over t...

Polar Rashba-type semiconductor BiTeI doped with magnetic elements constitutes one of the most promising platforms for the future development of spintronics and quantum computing thanks to the combination of strong spin-orbit coupling and internal ferromagnetic ordering. The latter originates from magnetic impurities and is able to open an energy g...

In present work, the effect of Pb1-xSnxTe (111) surface chemical treatment on electrophysical and optical properties was studied. It was shown that treatment of Pb1-xSnxTe (111) surface in HCl-isopropanol (HCl-iPA) solution led to removal of native oxides and surface enrichment by elemental tellurium of several nm thickness. Subsequent anneals in v...

Recently discovered intrinsic antiferromagnetic topological insulator MnBi$_2$Te$_4$ presents an exciting platform for realization of the quantum anomalous Hall effect and a number of related phenomena at elevated temperatures. An important characteristic making this material attractive for applications is its predicted large magnetic gap at the Di...

When intense lightwaves accelerate electrons through a solid, the emerging high-order harmonic (HH) radiation offers key insights into the material1–11. Sub-optical-cycle dynamics—such as dynamical Bloch oscillations2–5, quasiparticle collisions6,12, valley pseudospin switching¹³ and heating of Dirac gases¹⁰—leave fingerprints in the HH spectra of...

Heterostructures of Bi2Se3 topological insulators were epitaxially grown on graphene by means of the physical vapor deposition at 500 °C. Micrometer-sized flakes with thickness 1 QL (quintuple layer ~ 1 nm) and films of millimeter-scale with thicknesses 2–6 QL had been grown on CVD graphene. The minimum thickness of large-scaled continuous Bi2Se3 f...

The concept of an imaging-type 3D spin detector, based on the combination of spin-exchange interactions in the ferromagnetic (FM) film and spin selectivity of the electron–photon conversion effect in a semiconductor heterostructure, is proposed and demonstrated on a model system. This novel multichannel concept is based on the idea of direct transf...

We investigate the coupled spin and orbital textures of the topological surface state in Bi2(Te,Se)3(0001) across full momentum space using spin- and angle-resolved photoelectron spectroscopy and relativistic one-step photoemission theory. For an approximately isotropic Fermi surface in Bi2Te2Se, the measured intensity and spin momentum distributio...

We investigate the coupled spin and orbital textures of the topological surface state in Bi 2 (Te,Se) 3 (0001) across full momentum space using spin-and angle-resolved photoelectron spectroscopy and relativistic one-step photoemission theory. For an approximately isotropic Fermi surface in Bi 2 Te 2 Se, the measured intensity and spin momentum dist...

Narrow-gap semiconductors with strong spin-orbit coupling such as bismuth tellurohalides have become popular candidates for spintronic applications. But driving spin-polarized photocurrents in these materials with circularly polarized light requires picosecond lifetimes of the photoexcited carriers and low spin-flip scattering rates. In search of t...

We have grown the phase-homogeneous quaternary compound Bi1.1Sb0.9Te2S by the addition of Sb to Bi2Te2S which changed the conductivity from n- to p-type. Far-infrared optical and angle resolved photoemission spectra revealed a wide-band-gap three-dimensional topological insulator phase. The surface electronic spectrum is characterized by the topolo...

Feasibility of many emergent phenomena that intrinsic magnetic topological insulators (TIs) may host depends crucially on our ability to engineer and efficiently tune their electronic and magnetic structures. Here we report on a large family of intrinsic magnetic TIs in the homologous series of the van der Waals compounds (MnBi2Te4)(Bi2Te3)m with m...

The energy gap was revealed in the Dirac cone of the BiSbTeSe2 topological insulator after the submonolayer deposition of a ferromagnetic metal. As a ferromagnet, cobalt and manganese were used. Such way of the energy gap opening is novel in comparison to the bulk ferromagnetic doping of topological insulators.

SKIF is a synchrotron facility to be commissioned in 2024. One of the six beamlines planned to be built in the first phase is the "Electronic Structure" beamline. Now three branch lines are funded, which will host the endstations for Near Ambient Pressure X-Ray Photoelectron Spectroscopy (NAP XPS), Spin-Angle Resolved Photo-Emission Spectroscopy (S...

The experimental evidence of the influence of the structural phase transition on the elastic and optoelectronic properties of CH$_3$NH$_3$PbI$_3$ single crystals has been reported. A peak in the attenuation for longitudinal and shear ultrasonic waves and a step-like anomaly in their velocity have been found near the structural the orthorhombic-to-t...

Ferromagnetic materials are the widely used source of spin-polarized electrons in spintronic devices, which are controlled by external magnetic fields or spin-transfer torque methods. However, with increasing demand for smaller and faster spintronic components, utilization of spin-orbit phenomena provides promising alternatives. New materials with...

Non-reciprocal transport, where the left to right flowing current differs from the right to left flowing one, is an unexpected phenomenon in bulk crystals. BiTeBr is a non-centrosymmetric material, with a giant Rashba spin-orbit coupling which presents this unusual effect when placed in an in-plane magnetic field. It has been shown that this effect...

Chalcogenide phase-change materials show strikingly contrasting optical and electrical properties, which has led to their extensive implementation in various memory devices. By performing spin-, time-, and angle-resolved photoemission spectroscopy combined with the first-principles calculation, we report the experimental results that the crystallin...

Vanadium doped Bi2−x Te2.4Se0.6 single crystals, with x = 0.015 and 0.03, are grown by the Bridgman method. Bandstructure characterization by angle‐resolved photoemission spectroscopy (ARPES) measurements shows gapless topological surface states for both Vanadium concentrations. The Van‐der‐Pauw resistivity, the Hall charge carrier density and the...

Ferromagnetic materials are the widely used source of spin-polarized electrons in spintronic devices, which are controlled by external magnetic fields or spin-transfer torque methods. However, with increasing demand for smaller and faster spintronic components, utilization of spin-orbit phenomena provides promising alternatives. New materials with...

Thin Bi2Se3 films were deposited on mica substrates by physical vapor deposition without the use of the carrier gas. It was found that the films with high structural quality and high conductivity are grown at a source temperature of approximately 500 °C. The resistance of 20-300 nm thick films is in the range of 10²-10⁴ Ω/sq as compared with ∼10 Ω/...

Sub-angstrom Co coverage, being deposited on BiSbTeSe2(0001) surface at 200-330 C, opens a band gap at the Dirac point, with the shift of the Dirac point position caused by RT adsorbate pre-deposition. Temperature dependent measurements in 15-150 K range have shown no band gap width change. This fact indicates the nonmagnetic nature of the gap whic...

Thin Bi2Se3 flakes with few nanometer thicknesses and sized up to 350 m were created by using the electrochemical splitting from high-quality Bi2Se3 bulk monocrystals. The dependence of film resistance on the Bi2Se3 flake thickness demonstrates that, at room temperature, the bulk conductivity becomes negligible in comparison with the surface condu...

High-resistance Pb1 –xSnxTe〈In〉 layers grown by molecular beam epitaxy on BaF2(111) substrates with compositions close to band inversion have been investigated. The I–V characteristics and relaxation dependences of the photocurrent of the structures in dependence on the chemical surface treatment and subsequent exposure of the samples in air have b...

The studies of the structural transformation of BiSbTeSe 2 topological insulator during Co deposition were carried out. It was shown that Co, being deposited on BiSbTeSe 2 (0001) at 330°C, substantially modifies topmost part of the substrate. Reciprocal space mapping studies using RHEED data analysis reveal formation of the well-ordered layer with...

Controlled extraction of spin-polarized currents from the surface of topological insulators (TIs) would be an important step to use TIs as spin-electronic device materials. One way is to utilize the surface photovoltage (SPV) effect, by which the surface current may flow upon irradiation of light. To date, unipolar SPV has been observed on TIs, whi...

Quantum states of matter combining non-trivial topology and magnetism attract a lot of attention nowadays; the special focus is on magnetic topological insulators (MTIs) featuring quantum anomalous Hall and axion insulator phases. Feasibility of many novel phenomena that \emph{intrinsic} magnetic TIs may host depends crucially on our ability to eng...

Electronic correlation is believed to play an important role in exotic phenomena such as insulator-metal transition, colossal magneto resistance and high temperature superconductivity in correlated electron systems. Recently, it has been shown that electronic correlation may also be responsible for the formation of unconventional plasmons. Herewith...

Electronic correlation is believed to play an important role in exotic phenomena such as insulator-metal transition, colossal magnetoresistance, and high-temperature superconductivity in correlated electron systems. Recently, it has been shown that electronic correlation may also be responsible for the formation of unconventional plasmons. Herewith...