A. Alfonsov

activity

20062026

most citedPrediction and observation of the first antiferromagnetic topological insulator

1.2k citations · 1.9k across the 28 of their papers we have counts for

collaborators

29 papers

cond-mat.str-el2026

Magnetism in antiperovskite (Li $_{2}$ \textit{M})\textit{Ch}O (\textit{M} = Fe, Mn, Co; \textit{Ch} = S, Se) diluted magnets with fixed 1/3 filling: the key role of magnetic anisotropy

Jieyuan Zheng, Frederik L. Carstens, Lennart Singer +7

We report the magnetic properties of a series of lithium-rich antiperovskites (Li $_{2} M$ ) $C h$ O ( $M$ = Fe, Co, Mn and $C h$ = Se, S) where transition metal and lithium ions are randoml…

cond-mat.str-el2026

Magnetic anisotropy in the near-stoichiometric van der Waals ferromagnet Fe $_{3}$ GeTe $_{2}$

Riju Pal, Joyal John Abraham, Satyabrata Bera +5

Quasi-two-dimensional (2D) van der Waals (vdW) ferromagnets such as the series Fe $_{3 - x}$ GeTe $_{2}$ , with a relatively high Curie temperature and robust metallicity, offer an ideal p…

cond-mat.str-el2026

Spin-chiral electron-phonon coupling in metallic strontium titanate

N. Somun, L. Rogić, I. Khayr +12

Electron-phonon coupling (EPC) - the interaction between conduction electrons and quantized atomic vibrations - plays a central role in condensed matter physics and determines some…

cond-mat.str-el2026★ 3 cited

Magnetic-field tuning of the spin dynamics in the quasi-2D van der Waals antiferromagnet CuCrP $_{2}$ S $_{6}$

Joyal John Abraham, Yaqian Guo, Yuliia Shemerliuk +14

The use of antiferromagnets in magnetoelectronic devices as counterparts of ferromagnets is a new, rapidly developing trend in spintronics that leverages antiferromagnetic (AFM) ma…

cond-mat.str-el2025★ 16 cited

Disentangling the unusual magnetic anisotropy of the near-room-temperature ferromagnet Fe $_{4}$ GeTe $_{2}$

Riju Pal, Joyal J. Abraham, Alexander Mistonov +9

In the quest for two-dimensional conducting materials with high ferromagnetic ordering temperature the new family of the layered Fe $_{n}$ GeTe $_{2}$ compounds, especially the near-r…

cond-mat.str-el2025★ 3 cited

Ferromagnetic Resonance Spectroscopy on the Kagome Magnet MgMn $_{6}$ Sn $_{6}$

Riju Pal, Kakan Deb, Nitesh Kumar +3

MgMn $_{6}$ Sn $_{6}$ is the itinerant ferromagnet on the kagome lattice with high ordering temperature featuring complex electronic properties due to the nontrivial topological electroni…

cond-mat.str-el2024★ 11 cited

Electron Spin Resonance Spectroscopy on Magnetic Van der Waals Compounds

Vladislav Kataev, Bernd Büchner, Alexey Alfonsov

The field of research on magnetic van der Waals compounds -- a special subclass of quasi-two-dimensional materials -- is currently rapidly expanding due to the relevance of these c…

cond-mat.str-el2022

Magnetic resonance study of rare-earth titanates

Ana Najev, Sajna Hameed, Alexey Alfonsov +5

We present a nuclear magnetic resonance (NMR) and electron spin resonance (ESR) study of rare-earth titanates derived from the spin-1/2 Mott insulator YTiO $_{3}$ . Measurements of sin…

cond-mat.str-el2021★ 22 cited

Low-energy excitations and magnetic anisotropy of the layered van der Waals antiferromagnet Ni $_{2}$ P $_{2}$ S $_{6}$

K. Mehlawat, A. Alfonsov, S. Selter +4

The quasi-two-dimensional antiferromagnet Ni $_{2}$ P $_{2}$ S $_{6}$ belongs to the family of magnetic van der Waals compounds that provides a rich material base for the realization of funda…

cond-mat.str-el2021★ 26 cited

Magnetic field tuning of the spin dynamics in the magnetic topological insulators (MnBi $_{2}$ Te $_{4}$ )(Bi $_{2}$ Te $_{3}$ ) $_{n}$

A. Alfonsov, K. Mehlawat, A. Zeugner +3

We report a high frequency/high magnetic field electron spin resonance (HF-ESR) spectroscopy study in the sub-THz frequency domain of the two representatives of the family of magne…

cond-mat.str-el2021★ 35 cited

Frustration enhanced by Kitaev exchange in a $j ~_{eff} = \frac{1}{2}$ triangular antiferromagnet

C. Wellm, W. Roscher, J. Zeisner +9

Triangular Heisenberg antiferromagnets are prototypes of geometric frustration, even if for nearest-neighbor interactions quantum fluctuations are not usually strong enough to dest…

cond-mat.str-el2021★ 27 cited

Strongly anisotropic spin dynamics in magnetic topological insulators

A. Alfonsov, J. I. Facio, K. Mehlawat +8

The recent discovery of magnetic topological insulators has opened new avenues to explore exotic states of matter that can emerge from the interplay between topological electronic…

cond-mat.str-el2021★ 30 cited

Pressure control of the magnetic anisotropy of the quasi-two-dimensional van der Waals ferromagnet Cr $_{2}$ Ge $_{2}$ Te $_{6}$

T. Sakurai, B. Rubrecht, L. T. Corredor +10

We report the results of the pressure-dependent measurements of the static magnetization and of the ferromagnetic resonance (FMR) of Cr $_{2}$ Ge $_{2}$ Te $_{6}$ to address the properties of…

cond-mat.mtrl-sci2020★ 39 cited

Electron spin resonance and ferromagnetic resonance spectroscopy in the high-field phase of the van der Waals magnet CrCl $_{3}$

J. Zeisner, K. Mehlawat, A. Alfonsov +5

We report a comprehensive high-field/high-frequency electron spin resonance (ESR) study on single crystals of the van der Waals magnet CrCl $_{3}$ . This material, although being known…

cond-mat.str-el2020★ 28 cited

Long-range magnetic order in the $S ~ = 1/2$ triangular lattice antiferromagnet KCeS $_{2}$

G. Bastien, B. Rubrecht, E. Haeussler +19

Recently, several putative quantum spin liquid (QSL) states were discovered in $S ~ = 1/2$ rare-earth based triangular-lattice antiferromagnets (TLAF) with the delafossite s…

cond-mat.str-el2019★ 21 cited

Magnetic interactions in the tripod-kagome antiferromagnet Mg $_{2}$ Gd $_{3}$ Sb $_{3}$ O $_{14}$ probed by static magnetometry and high-field ESR spectroscopy

C. Wellm, J. Zeisner, A. Alfonsov +7

We report an experimental study of the static magnetization $M (H, T)$ and high-field electron spin resonance (ESR) of polycrystalline \MgGd, a representative member of the newly dis…

cond-mat.mtrl-sci2019★ 131 cited

Topological electronic structure and intrinsic magnetization in MnBi $_{4}$ Te $_{7}$ : a Bi $_{2}$ Te $_{3}$ -derivative with a periodic Mn sublattice

Raphael C. Vidal, Alexander Zeugner, Jorge I. Facio +23

Combinations of non-trivial band topology and long-range magnetic order hold promise for realizations of novel spintronic phenomena, such as the quantum anomalous Hall effect and t…

cond-mat.str-el2018★ 82 cited

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr $_{2}$ Ge $_{2}$ Te $_{6}$

J. Zeisner, A. Alfonsov, S. Selter +6

We report a comprehensive experimental investigation on the magnetic anisotropy in bulk single crystals of Cr $_{2}$ Ge $_{2}$ Te $_{6}$ , a quasi-two-dimensional ferromagnet belonging to the…

cond-mat.mtrl-sci2018★ 1.2k cited

Prediction and observation of the first antiferromagnetic topological insulator

Mikhail M. Otrokov, Ilya I. Klimovskikh, Hendrik Bentmann +41

Magnetic topological insulators (MTIs) are narrow gap semiconductor materials that combine non-trivial band topology and magnetic order. Unlike their nonmagnetic counterparts, MTIs…

cond-mat.str-el2017★ 55 cited

Signatures of low-energy fractionalized excitations in $α$ -RuCl $_{3}$ from field-dependent microwave absorption

C. Wellm, J. Zeisner, A. Alfonsov +7

Topologically ordered states of matter are generically characterized by excitations with quantum number fractionalization. A prime example is the spin liquid realized in Kitaev's h…

cond-mat.str-el2016★ 4 cited

Cantilever detected ferromagnetic resonance in thin Fe $_{50}$ Ni $_{50}$ , Co $_{2}$ FeAl $_{0.5}$ Si $_{0.5}$ and Sr $_{2}$ FeMoO $_{6}$ films using a double modulation technique

Alexey Alfonsov, Eiji Ohmichi, Pavel Leksin +5

In this work we introduce a new method of a ferromagnetic resonance (FMR) detection from thin, nm-size, films. Our setup is based on the commercial piezo-cantilever, used for atomi…

cond-mat.str-el2016★ 2 cited

Tuning the magnetocrystalline anisotropy in $R$ CoPO by means of $R$ substitution: a ferromagnetic resonance study

G. Prando, A. Alfonsov, A. Pal +3

We report on broad-band electron spin resonance measurements performed within the itinerant ferromagnetic phase of $R$ CoPO ( $R$ = La, Pr, Nd and Sm). We reveal that the $R$ substit…

cond-mat.str-el2013★ 50 cited

Low energy magnetic excitations in the spin-orbital Mott insulator Sr $_{2}$ IrO $_{4}$

S. Bahr, A. Alfonsov, G. Jackeli +6

We report a high-field electron spin resonance study in the sub-THz frequency domain of a single crystal of Sr $_{2}$ IrO $_{4}$ that has been recently proposed as a prototypical spin-orb…

cond-mat.mtrl-sci2013★ 8 cited

Nuclear magnetic resonance study of thin Co $_{2}$ FeAl $_{0.5}$ Si $_{0.5}$ Heusler films with varying thickness

A. Alfonsov, B. Peters, F. Y. Yang +2

Type, degree and evolution of structural order are important aspects for understanding and controlling the properties of highly spin polarized Heusler compounds, in particular with…

Magnetism in antiperovskite (Li2​\textit{M})\textit{Ch}O (\textit{M} = Fe, Mn, Co; \textit{Ch} = S, Se) diluted magnets with fixed 1/3 filling: the key role of magnetic anisotropy

Magnetic anisotropy in the near-stoichiometric van der Waals ferromagnet Fe3​GeTe2​

Spin-chiral electron-phonon coupling in metallic strontium titanate

Magnetic-field tuning of the spin dynamics in the quasi-2D van der Waals antiferromagnet CuCrP2​S6​

Disentangling the unusual magnetic anisotropy of the near-room-temperature ferromagnet Fe4​GeTe2​

Ferromagnetic Resonance Spectroscopy on the Kagome Magnet MgMn6​Sn6​

Electron Spin Resonance Spectroscopy on Magnetic Van der Waals Compounds

Magnetic resonance study of rare-earth titanates

Low-energy excitations and magnetic anisotropy of the layered van der Waals antiferromagnet Ni2​P2​S6​

Magnetic field tuning of the spin dynamics in the magnetic topological insulators (MnBi2​Te4​)(Bi2​Te3​)n​

Frustration enhanced by Kitaev exchange in a j~​eff​=21​ triangular antiferromagnet

Strongly anisotropic spin dynamics in magnetic topological insulators

Pressure control of the magnetic anisotropy of the quasi-two-dimensional van der Waals ferromagnet Cr2​Ge2​Te6​

Electron spin resonance and ferromagnetic resonance spectroscopy in the high-field phase of the van der Waals magnet CrCl3​

Long-range magnetic order in the S~=1/2 triangular lattice antiferromagnet KCeS2​

Magnetic interactions in the tripod-kagome antiferromagnet Mg2​Gd3​Sb3​O14​ probed by static magnetometry and high-field ESR spectroscopy

Topological electronic structure and intrinsic magnetization in MnBi4​Te7​: a Bi2​Te3​-derivative with a periodic Mn sublattice

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr2​Ge2​Te6​

Prediction and observation of the first antiferromagnetic topological insulator

Signatures of low-energy fractionalized excitations in α-RuCl3​ from field-dependent microwave absorption

Cantilever detected ferromagnetic resonance in thin Fe50​Ni50​, Co2​FeAl0.5​Si0.5​ and Sr2​FeMoO6​ films using a double modulation technique

Tuning the magnetocrystalline anisotropy in RCoPO by means of R substitution: a ferromagnetic resonance study

Low energy magnetic excitations in the spin-orbital Mott insulator Sr2​IrO4​

Nuclear magnetic resonance study of thin Co2​FeAl0.5​Si0.5​ Heusler films with varying thickness

Magnetism in antiperovskite (Li $_{2}$ \textit{M})\textit{Ch}O (\textit{M} = Fe, Mn, Co; \textit{Ch} = S, Se) diluted magnets with fixed 1/3 filling: the key role of magnetic anisotropy

Magnetic anisotropy in the near-stoichiometric van der Waals ferromagnet Fe $_{3}$ GeTe $_{2}$

Magnetic-field tuning of the spin dynamics in the quasi-2D van der Waals antiferromagnet CuCrP $_{2}$ S $_{6}$

Disentangling the unusual magnetic anisotropy of the near-room-temperature ferromagnet Fe $_{4}$ GeTe $_{2}$

Ferromagnetic Resonance Spectroscopy on the Kagome Magnet MgMn $_{6}$ Sn $_{6}$

Low-energy excitations and magnetic anisotropy of the layered van der Waals antiferromagnet Ni $_{2}$ P $_{2}$ S $_{6}$

Magnetic field tuning of the spin dynamics in the magnetic topological insulators (MnBi $_{2}$ Te $_{4}$ )(Bi $_{2}$ Te $_{3}$ ) $_{n}$

Frustration enhanced by Kitaev exchange in a $j ~_{eff} = \frac{1}{2}$ triangular antiferromagnet

Pressure control of the magnetic anisotropy of the quasi-two-dimensional van der Waals ferromagnet Cr $_{2}$ Ge $_{2}$ Te $_{6}$

Electron spin resonance and ferromagnetic resonance spectroscopy in the high-field phase of the van der Waals magnet CrCl $_{3}$

Long-range magnetic order in the $S ~ = 1/2$ triangular lattice antiferromagnet KCeS $_{2}$

Magnetic interactions in the tripod-kagome antiferromagnet Mg $_{2}$ Gd $_{3}$ Sb $_{3}$ O $_{14}$ probed by static magnetometry and high-field ESR spectroscopy

Topological electronic structure and intrinsic magnetization in MnBi $_{4}$ Te $_{7}$ : a Bi $_{2}$ Te $_{3}$ -derivative with a periodic Mn sublattice

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr $_{2}$ Ge $_{2}$ Te $_{6}$

Signatures of low-energy fractionalized excitations in $α$ -RuCl $_{3}$ from field-dependent microwave absorption

Cantilever detected ferromagnetic resonance in thin Fe $_{50}$ Ni $_{50}$ , Co $_{2}$ FeAl $_{0.5}$ Si $_{0.5}$ and Sr $_{2}$ FeMoO $_{6}$ films using a double modulation technique

Tuning the magnetocrystalline anisotropy in $R$ CoPO by means of $R$ substitution: a ferromagnetic resonance study

Low energy magnetic excitations in the spin-orbital Mott insulator Sr $_{2}$ IrO $_{4}$

Nuclear magnetic resonance study of thin Co $_{2}$ FeAl $_{0.5}$ Si $_{0.5}$ Heusler films with varying thickness