arXiv subjects

L. X. Yang

Publications and source records attributed to L. X. Yang.

57 records · Page 4Linked to original sources

arXiv2005

High-Pressure Induced Structural Phase Transition in CaCrO4: Evidence from Raman Scattering Studies

Raman spectroscopic studies have been carried out on CaCrO4 under pressure up to 26GPa at ambient temperature. The Raman spectra showed CaCrO4 experienced a continuous structural phase transition started at near 6GPa, and finished at about 10GPa. It is found that the high-pressure phase could be quenched to ambient conditions. Pressure dependence of the Raman peaks suggested there existed four pressure regions related to different structural characters. We discussed these characters and inferred that the nonreversible structural transition in CaCrO4, most likely was from a zircon-type (I41/amd) ambient phase to a scheelite-type high pressure structure (I41/a).

cond-mat.mtrl-sci↗

arXiv2005

Isostructural Phase Transition of TiN Under High Pressure

In situ high-pressure energy dispersive x-ray diffraction experiments on polycrystalline powder TiN with NaCl-type structure have been conducted with the pressure up to 30.1 GPa by using the diamond anvil cell instrument with synchrotron radiation at room tempearture. The experimental results suggested that an isostructural phase transition might exist at about 7 GPa as revealed by the discontinuity of V/V0 with pressure.

cond-mat.mtrl-sci↗

arXiv2004

Phase separation, effects of magnetic field and high pressure on charge ordering in y-Na0.5CoO2

Transmission electron microscopy observations reveal the presence of complex superstructures and remarkable phase separation in association with Na-ordering phenomenon in y-Na0.5CoO2. Resistivity and magnetization measurements indicate that three phase transitions at the temperatures of 25 K, 53 K and 90 K respectively appear commonly in y-Na0.5CoO2 samples. Under a high pressure up to 10 Kbar, the low-temperature transport properties show certain changes below the charge order transition; under an applied magnetic field of 7 Tesla, phase transitions at around 25 K and 53 K, proposed fundamentally in connection with alternations of magnetic structure and charge ordering maintain almost unchanged.

cond-mat.str-el↗