Publications de Sergiy Katrych

High-Pressure Synthesis of Rare-Earth Borate-Nitrate Crystals for Second Harmonic Generation

László Forró, Andrzej Sienkiewicz, Alla Arakcheeva, Sergiy Katrych, Trpimir Ivsic

The crystals of a novel family of rare-earth borate-nitrate compounds, Ln(7)(BO3)(3) (NO3)N3O (Ln = Pr, Nd), were grown at high-pressure in KAs flux and their crystal structure was determined. The new type of the crystalline structure consists of parallel ...

AMER CHEMICAL SOC2021

Decoupling of lattice and orbital degrees of freedom in an iron-pnictide superconductor

László Forró, Qian Wang, Johan Juul Chang, Sergiy Katrych

The interplay between structural and electronic phases in iron-based superconductors is a central theme in the search for the superconducting pairing mechanism. While electronic nematicity is competing with superconductivity, the effect of purely structura ...

AMER PHYSICAL SOC2021

Thermal coarsening of individual titanate nanowires and their assemblies: Surface vs. bulk diffusion

Luca Rossi, László Forró, Xavier Berdat, Massimo Spina, Endre Horvath, Laurent Syavoch Bernard, Sergiy Katrych

The thermal coarsening of titanate nanowires was investigated from room temperature to 1000 degrees C by AFM, SEM, XRD and Raman spectroscopy. Phase transformation kinetics and the external morphology were studied in two configurations: i) as individual an ...

2020

Persistent antiferromagnetic order in heavily overdoped Ca1-xLaxFeAs2

László Forró, Ana Akrap, Henrik Moodysson Rønnow, Ivica Zivkovic, Sergiy Katrych, Edoardo Martino, Philip Johannes Walter Moll, Maja Deborah Bachmann

In the Ca1-xLaxFeAs2 (1 1 2) family of pnictide superconductors, we have investigated a highly overdoped composition (x = 0.56), prepared by a high-pressure, high-temperature synthesis. Magnetic measurements show an antiferromagnetic transition at T-N = 12 ...

2019

The influence of the incommensurately modulated structure on the physical properties of Fe1.35Ge

Helmuth Berger, László Forró, Alla Arakcheeva, Philip Pattison, Krunoslav Prsa, Jacim Jacimovic, Sergiy Katrych, Andrea Pisoni

Single crystal growth by chemical vapour transport has resulted samples with Fe1.35Ge stoichiometry. Structural study has shown that the large number of vacancies introduces an incommensuately modulated structure. The electrical resistivity is in the 200 m ...

2019

Electronic properties of incommensurately modulated novel and complex materials

László Forró, Oleg Yazyev, Alla Arakcheeva, Ana Akrap, Gabriel Albert Autes, Sergiy Katrych, Edoardo Martino, Philip Johannes Walter Moll

INT UNION CRYSTALLOGRAPHY2018

Single crystals of superconducting SmFeAsOHx: Structure and properties

László Forró, Richard Gaal, Alla Arakcheeva, Sergiy Katrych, Janusz Andrzej Karpinski, Andrea Pisoni, Ping Huang, Péter Krisztián Matus

We report the synthesis, structure, and superconducting properties of single crystals of SmFeAsOHx. The crystals were grown at high pressure and high temperature using a cubic anvil technique. H-1-NMR studies confirm the presence of H atoms in the samples. ...

Amer Physical Soc2016

Upper critical field, pressure-dependent superconductivity and electronic anisotropy of Sm4Fe2As2Te1-xO4-yFy

László Forró, Richard Gaal, Bálint Náfrádi, Sergiy Katrych, Janusz Andrzej Karpinski, Andrea Pisoni, Péter Szirmai

We present a detailed study of the electrical transport properties of a recently discovered iron-based superconductor: Sm4Fe2As2Te0.72O2.8F1.2. We followed the temperature dependence of the upper critical field by resistivity measurement of single crystals ...

Iop Publishing Ltd2016

Magnetotransport studies of superconducting Pr4Fe2As2Te1-xO4

László Forró, Richard Gaal, Bálint Náfrádi, Sergiy Katrych, Janusz Andrzej Karpinski, Andrea Pisoni, Péter Szirmai

We report a study of the electrical transport properties of single crystals of Pr(4)Fe(2)As(2)Te(1-)xO(4), a recently discovered iron-based superconductor. Resistivity, Hall effect, and magnetoresistance are measured in a broad temperature range revealing ...

Amer Physical Soc2016

Possibility of an unconventional spin state of Ir4+ in Ba21Ir9O43 single crystal

László Forró, Arnaud Magrez, Oleg Yazyev, Alla Arakcheeva, Bálint Náfrádi, Henrik Moodysson Rønnow, Ivica Zivkovic, Jacim Jacimovic, Sergiy Katrych, Andrea Pisoni, Lin Yang, Noore Elahi Shaik

We report the synthesis of single crystals of a novel layered iridate Ba21Ir9O43 and present the crystallographic, transport, and magnetic properties of this material. The compound has a hexagonal structure with two iridium oxide layers stacked along the c ...

Amer Physical Soc2016

Local lattice distortions vs. structural phase transition in NdFeAsO1-xFx

Sergiy Katrych, Janusz Andrzej Karpinski

The lattice properties at low temperatures of two samples of NdFeAsO1-xFx (x = 0.05 and 0.25) have been examined in order to investigate possible structural phase transition that may occur in the optimally doped superconducting sample with respect to the n ...

Elsevier2016

Slow magnetic fluctuations and superconductivity in fluorine-doped NdFeAsO

Sergiy Katrych, Janusz Andrzej Karpinski

Among the widely studied superconducting iron-pnictide compounds belonging to the Ln1111 family (with Ln a lanthanide), a systematic investigation of the crossover region between the superconducting and the antifer-romagnetic phase for the Ln = Nd case has ...

Amer Physical Soc2015

Crystal Structure, Transport, and Magnetic Properties of an Ir6+ Compound Ba8Al2IrO14

László Forró, Arnaud Magrez, Alla Arakcheeva, Bastien Dalla Piazza, Ana Akrap, Krunoslav Prsa, Henrik Moodysson Rønnow, Jacim Jacimovic, Sergiy Katrych, Andrea Pisoni, Lin Yang

The novel iridate Ba8Al2IrO14 was prepared as single crystals by self-flux method, thereby providing a rare example of an all-Ir(VI) compound that can be synthesized under ambient pressure conditions. The preparation of all-Ir6+ iridate without using tradi ...

2015

Magnetic field penetration in MgB2 single crystals: Pinning and Meissner holes

Sergiy Katrych, Janusz Andrzej Karpinski

The evolution of flux distribution in MgB2 single crystals during their remagnetization was imaged with magneto-optical technique. Meissner holes, formed as the areas where the annihilation of vortices and antivortices takes place, were found at the bounda ...

Amer Inst Physics2014

Critical current anisotropy in Nd-1111 single crystals and the influence of neutron irradiation

Sergiy Katrych, Janusz Andrzej Karpinski

We report on angle-resolved magnetization measurements on NdFeAsO0.65F0.35 ( Nd-1111) single crystals. The field dependence of the critical current density, Jc, is non-monotonic in these crystals at all orientations and temperatures due to the fishtail eff ...

Iop Publishing Ltd2014

Enhanced low-temperature thermoelectrical properties of BiTeCl grown by topotactic method

Helmuth Berger, Philippe Bugnon, László Forró, Richard Gaal, Arnaud Magrez, Ana Akrap, Jacim Jacimovic, Xavier François Mettan, Sergiy Katrych, Andrea Pisoni

We developed a topotactic strategy to grow BiTeCl single crystals. Structural characterization by means of X-ray diffraction was performed, and the high crystallinity of the material was proven. Measurements of the thermoelectrical coefficients electrical ...

Pergamon-Elsevier Science Ltd2014

L4Fe2As2Te1-xO4-yFy (L = Pr, Sm, Gd): A layered oxypnictide superconductor with T-c up to 45 K

László Forró, Richard Gaal, Sergiy Katrych, Janusz Andrzej Karpinski, Andrea Pisoni

The synthesis and structural and physical properties of iron lanthanide oxypnictide superconductors, L4Fe2As2Te1-xO4 (L = Pr, Sm, Gd), with transition temperature at similar to 25 K are reported. Single crystals have been grown at high pressure using the c ...

Amer Physical Soc2014

Huge critical current density and tailored superconducting anisotropy in SmFeAsO0.8F0.15 by low-density columnar-defect incorporation

Sergiy Katrych, Janusz Andrzej Karpinski, Yihan Jia

Iron-based superconductors could be useful for electricity distribution and superconducting magnet applications because of their relatively high critical current densities and upper critical fields. SmFeAsO0.8F0.15 is of particular interest as it has the h ...

Nature Publishing Group2013

Pr4Fe2As2Te1-xO4: A layered FeAs-based superconductor

László Forró, Richard Gaal, Sergiy Katrych, Janusz Andrzej Karpinski, Andrea Pisoni

We report crystal growth at high pressure, structure determination, and magnetic and transport studies of an oxypnictide superconductor Pr4Fe2As2Te1-xO4. Its structure resembles the known 1111 phase except for the considerably larger c lattice constant and ...

Amer Physical Soc2013

Conventional superconductivity and hysteretic Campbell penetration depth in single crystals MgCNi3

Sergiy Katrych

Single crystals of MgCNi3, with areas sized up to 1 mm(2), were grown by the self-flux method using a cubic anvil high-pressure technique. In low applied fields, the dc magnetization exhibited a very narrow transition into the superconducting state, demons ...

Amer Physical Soc2013