اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدLow temperature Synchrotron X-ray diffraction studies on spin lattice coupling in Co3TeO6 and Co2.5Mn0.5TeO6
114
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
In the quest of understanding significant variations in the physical, chemical and electronic properties of the novel functional materials, low temperature Synchrotron X-ray Diffraction (LT-SXRD) measurements on CTO (a type-II) and CMTO (a type-I) multiferroics are presented. Magnetic phase diagram of CTO shows multiple magnetic transitions at zero fields, whereas, in CMTO, 20 K enhancement in the antiferromagnetic transition temperature is observed followed by near room temperature Griffiths phase. Rietveld analysis on LT-SXRD data of both the samples indicates important observations. For both CTO and CMTO, the magnetic anomalies are followed by structural anomalies, which is a clear signature of spin lattice coupling and the positive shift of spin lattice coupling from CTO to CMTO.
قيم البحث
اقرأ أيضاً
The transformation between the metallic ($beta$) and semi-conducting ($alpha$) allotropes of tin is still not well understood. The phase transition temperature stated in the literature, 286.2 K, seems to be inconsistent with recent calorimetric measu
rements. In this paper, this intriguing aspect has been explored in Sn and Sn-Cu (alloyed 0.5% Cu by weight) using temperature resolved synchrotron x-ray diffraction measurements performed at the Indus-2 facility. Additionally, the $alpha rightleftharpoons beta$ Sn transition has been recorded using in-situ heating/cooling experiments in a scanning electron microscope. Based on these measurements, a protocol has been suggested to reduce the formation of $alpha$-Sn in potentially susceptible systems. This will be useful in experiments like TIN.TIN (The INdia-based TIN detector), which proposes to employ ~100 - 1000 kg of superconducting tin-based detectors to search for neutrinoless double beta decay in the isotope $^{124}$Sn.
A two step solid state reaction route has been presented to synthesize monophasic cobalt tellurate (Co3TeO6, CTO) using Co3O4 and TeO2 as starting reagents. During synthesis, initial ingredient Co3O4 is found better than CoO in circumventing the inte
rmediate Co5TeO8 or CoTeO3 phases. High resolution Synchrotron X-ray Diffraction has been used to probe different phases present in synthesized CTO and to achieve its single phase. Further, XANES studies near Co K and Te L-edge reveal mixed oxidation states of Co (i.e. Co2+ and Co3+) and +VI valence state of Te respectively, which is also confirmed with XPS. Charge imbalance due to different oxidation states of the Co-ions has been observed to be compensated by plausible Te-cations vacancy. Enhanced multiferroic properties like effective magnetic moment (JAP 116, (2014)) have been correlated with the present synthesis route.
Two sets of amorphous carbon materials prepared at different routes are irradiated with swift (145 MeV) heavy ion (Ne6+). The structural parameters like the size of ordered grains along c and a axis i.e. Lc & La, the average spacing of the crystallog
raphic planes (002) i.e. d002 and the fraction of the amorphous phase of the unirradiated and the irradiated samples are estimated by X-ray diffraction technique. The fraction of the amorphous phase is generally found to increase with the irradiation dose for both sets of the samples. The estimated and values are found to be almost unaffected by irradiation. The estimated values of corroborate with the increase of disorder in both sets of the samples with the increasing dose of irradiation. Keywords: X-ray Diffraction, Amorphous Carbon, Irradiation
The microstructural parameters like the average domain size, effective domain size at a particular crystallographic direction and microstrain within the domains of titanium and Ti-5%Ta-2%Nb, irradiated with 116 MeV O5+ ion, have been characterized as
a function of dose by X-Ray Diffraction Line Profile Analysis using different model based approaches. Dislocation Density and stacking fault probabilities have also been estimated from the analysis. The analysis revealed that there was a significant decrease of the average domain size with dose as compared to the unirradiated sample. The estimated values of dislocation density increased significantly for the irradiated samples and was found to be an order of magnitude more as compared to the unirradiated one. However, the dislocation density saturated with increase in dose. The deformation (stacking) fault probabilities were found to be negligible even with the increase in dose of irradiation.
Resonant magnetic x-ray diffraction experiments were carried out on the stacked triangular lattice antiferromagnet GdPd2Al3. The experiments revealed an expected initial collinear c-axis order at TN1 followed by an additional in-plane order at TN2, w
hile at the same time we found that the ground state is a helically ordered state of a very long incommensurate period of approximately 700A. The distribution of K-domains was highly anisotropic, and the domain with the modulation vector normal to the surface of the crystal was ascendant. Low-field magnetization is discussed on the basis of the observed incommensurate magnetic structure.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
