NbS3_{3}: A unique quasi one-dimensional conductor with three charge density wave transitions

Through transport, compositional and structural studies, we review the features of the charge-density wave (CDW) conductor of NbS$_{3}$ (phase II). We highlight three central results: 1) In addition to the previously reported CDW transitions at $T_{P1}$ = 360\,K and $T_{P2}$ = 150\,K, another CDW transition occurs at a much higher temperature $T_{P0}$ = 620-650\,K; evidence for the non-linear conductivity of this CDW is presented. 2) We show that CDW associated with the $T_{P2}$ - transition arises from S vacancies acting as donors. Such a CDW transition has not been observed before. 3) We show exceptional coherence of the $T_{P1}$-CDW at room-temperature. Additionally, we report on the effects of uniaxial strain on the CDW transition temperatures and transport.Comment: 16 pages, 18 figure

Nb S3: A unique quasi-one-dimensional conductor with three charge density wave transitions

© 2017 American Physical Society.We review the features of the charge density wave (CDW) conductor NbS3 (phase II) and include several additional results from transport, compositional, and structural studies. Particularly, we highlight three central results: (1) In addition to the previously reported CDW transitions at TP1=360K and TP2=150K, a third CDW transition occurs at a much higher temperature TP0≈620-650K; evidence for the nonlinear conductivity of this CDW is presented. (2) We show that the CDW associated with the TP2 transition arises from S vacancies acting as donors. Such a CDW transition has not been observed before. (3) We demonstrate the exceptional coherence of the TP1 CDW at room temperature. The effects of uniaxial strain on the CDW transition temperature and transport are reported

Synthesis of the Orthorhombic Dy1-xHoxMnO3 Single Crystals and Study of Their Magnetic Properties

In this report we prepared for the first time the orthorhombic Dy1-xHoxMnO3 single crystals with x = 0, 0.1, 0.2, 0.3, and 0.4 using the flux technique. The post-growth processing and chemical and structural characterization of the synthesized samples were performed. Also we examined the samples obtained by their magnetic properties and the magnetic anisotropy in wide ranges of temperatures and magnetic fields

Дослідження характеристик вітчизняних радіонепрозорих тканин Н1, Н2 та Н3 при різних комбінаціях їхнього застосуванняі

Experimentally investigated the domestic radiopaque fabrics H1, H2 and H3 for determination of shielding factor for different combinations of the fabrics. Radar experimentally investigated tissue domestic production H1, H2 and H3 and determined the overall rate of screening for different variations of the combination of these tissues. The laboratory measurements have been performed in the frequency range taking into consideration the placing of the fibers. The results have been obtained for both horizontal and for vertical locations. For researches touching upon the antenna emitting device there are used several screening combinations of the fabrics: H1-H2, H3-H2 and H1-H3. The measurement results have showed that, for all combinations of the fabrics, the screening factor varies considerably through frequency band and depends on the location of the fabric fibers. Fig.: 6. Refs: 11 titles.Экспериментально исследованы радионепрозрачные ткани отечественного производства Н1, Н2 и Н3 и определен общий коэффициент экранирования при разных вариациях соединения этих тканей. Лабораторные измерения проводились в диапазоне частот с учетом размещения волокон, и результаты получены как для горизонтального, так и для вертикального расположения. Для исследований антенна излучающего устройства поочередно экранировалась тканями в разных комбинациях: Н1-Н2, Н2-Н3 и Н1-Н3. Результаты измерений показали, что у всех комбинаций тканей коэффициент экранирования значительно изменяется в полосе частот и в зависимости от расположения волокон ткани. Ил.: 6. Библиогр.: 11 наим.Експериментально досліджено радіонепрозорі тканини вітчизняного виробництва Н1, Н2 та Н3 і визначено загальний коефіцієнт екрану­вання при різних варіаціях поєднання цих тканин. Лабораторні виміри проведено у діапазоні частот з урахуванням розміщення волокон, ре­зультати отримано як для горизонтального, так і для вертикального розташування. Для досліджень антена випромінюючого пристрою по­чергово екранувалася тканинами в різних комбінаціях: Н1-Н2, Н2-Н3 та Н1-Н3. Результати вимірювань показали, що в усіх комбінаціях тканин коефіцієнт екранування значно змінюється у смузі частот і залежно від розташування волокон тканини

Gallium Composition-Dependent Structural Phase Transitions in HoFe3–xGax(BO3)4 Solid Solutions: Crystal Growth, Structure, and Raman Spectroscopy Study

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Single crystals of solid solutions of HoFe3–xGax(BO3)4 with x = 0, 0.5, 1, 1.5, and 3 were obtained using flux synthesis. The conditions of the synthesis are described in detail. The structural properties of each of the synthesized samples were studied using X-ray powder diffraction analysis at several temperature points (303, 403, and 503 K). The structural parameters of the obtained samples and the “pure” compounds HoFe3(BO3)4 and HoGa3(BO3)4 were compared. The Raman spectra of the obtained solid solutions HoFe3–xGax(BO3)4 were studied in a wide temperature range (T = 10–400 K). The vibrational spectra and eigenvectors of the HoFe3Ga(BO3)4 and HoGa3(BO3)4 in R32 phase and HoFe3Ga(BO3)4 in P3121 phase were calculated within density functional theory. The features of the Raman spectra of HoFe2Ga(BO3)4, HoFe2.5Ga0.5(BO3)4, HoFe3(BO3)4 crystals associated with the R32 → P3121 structural phase transition, which have a strong dependence on the degree of substitution x, were investigated. Peculiarities of the Raman spectra, which are associated with magnetic ordering in HoFe1.5Ga1.5(BO3)4, HoFe2Ga(BO3)4, and HoFe2.5Ga0.5(BO3)4 crystals, were detected

Complex interplay between 3d and 4f magnetic systems and magnetic chirality in multiferroic Dy1−x_{1-x}Hox_xMnO3_3 (x=0,0.2x = 0, 0.2)

Structural, magnetic and multiferroic properties of single crystals of Dy$_{1-x}$Ho$_x$MnO$_3$ ($x = 0, 0.2$) were investigated by the different methods of polarized and classical neutron diffraction and macroscopic methods in order to determine the effect of Ho doping on the magneto-electric behavior of the title compounds. It is shown that substitution by Ho of 20% on the position of Dy do not change overall crystal symmetry of compound. It remains of Pnma type for both compositions down to the very low temperatures. Magnetic ordering do not change the crystal structure. Precise magnetic order and it detailed temperature and field evolution both in the pristine and substituted compounds we determined using single crystal neutron diffraction and magnetization measurements. The results show a complex interplay between transition metal and rear earth magnetic sub lattices leading to so-called "Mn-controlled" and "Dy-controlled" magnetic states. Using polarized neutron diffraction 3D character of rear earth magnetic order in Dy$_{0.8}$Ho$_{0.2}$MnO$_3$ in contract to DyMnO$_3$ and occurrence of the chiral type magnetic structure on Mn subsystem could be revealed. The influence of the external electric field on the magnetic chirality could be directly evidenced, proving strong magneto-electric coupling in multiferroic phase. The study of the electric polarization under similar temperatures and fields on the same samples provides the direct correlation between the results of the microscopic and macroscopic investigations.Comment: 26 pages, 12 figures, 3 table

Complex interplay between 3d and 4f magnetic systems in multiferroic DyMnO3_3

Structural and magnetic properties of single crystals of DyMnO$_3$ were investigated by neutron diffraction in order to study the peculiarities of $3d$-$4f$ interactions in this compound. Precise magnetic order and its detailed temperature evolution were determined using single crystal neutron diffraction. Elliptical cycloid on manganese subsystem below $T_{Ch}$ = 19 K was confirmed, with temperature decrease the elipticity of the Mn magnetic structure reduces significantly, creating almost circular cycloid. Temperature evolution of the magnetic structure demonstrate specific hysteretic behavior. The results show a complex interplay between transition metal and rare earth magnetic sublattices leading to so-called “Mn- controlled” and “Dy- controlled” magnetic states. The strong and complicate $3d$-$4f$ interaction leads to the unusual very slow magnetic structure relaxation

Nb S3: A unique quasi-one-dimensional conductor with three charge density wave transitions

© 2017 American Physical Society.We review the features of the charge density wave (CDW) conductor NbS3 (phase II) and include several additional results from transport, compositional, and structural studies. Particularly, we highlight three central results: (1) In addition to the previously reported CDW transitions at TP1=360K and TP2=150K, a third CDW transition occurs at a much higher temperature TP0≈620-650K; evidence for the nonlinear conductivity of this CDW is presented. (2) We show that the CDW associated with the TP2 transition arises from S vacancies acting as donors. Such a CDW transition has not been observed before. (3) We demonstrate the exceptional coherence of the TP1 CDW at room temperature. The effects of uniaxial strain on the CDW transition temperature and transport are reported