Orbital change manipulation metal–insulator transition temperature in W-doped VO2

2015 ◽  
Vol 17 (17) ◽  
pp. 11638-11646 ◽  
Author(s):  
Xinfeng He ◽  
Yijie Zeng ◽  
Xiaofeng Xu ◽  
Congcong Gu ◽  
Fei Chen ◽  
...  

Using ultraviolet-infrared spectroscopy and first principles calculations, it is revealed that changes in the orbital structure can regulate the W-doped VO2 phase transition temperature.

RSC Advances ◽  
2020 ◽  
Vol 10 (32) ◽  
pp. 18543-18552 ◽  
Author(s):  
Lanli Chen ◽  
Yuanyuan Cui ◽  
Hongjie Luo ◽  
Yanfeng Gao

The controllable phase transition temperature in charge doping VO2 is coupled with changes in the atomic and electronic structures. The current results provide a variable way to tune the VO2 phase transition temperature through charge doping.


2019 ◽  
Vol 33 (12) ◽  
pp. 1950148
Author(s):  
Yongcheng Liang ◽  
Ping Qin ◽  
Zhiyong Liang ◽  
Lizhen Zhang ◽  
Xun Yuan ◽  
...  

Metal-insulator transition (MIT) underlies many remarkable and technologically important phenomena in VO2. Even though its monoclinic structure had before been the reserve of the insulating state, recent experiments have observed an unexpected monoclinic metallic state. Here, we use a modified approach combining first-principles calculations with orbital-biased potentials to reproduce the correct stability ordering and electronic structures of different phases of VO2. We identify a ferromagnetic monoclinic metal that is likely to be the experimentally observed mysterious metastable state. Furthermore, the calculations show that an isostructural insulator-metal electronic transition is followed by the lattice distortion from the monoclinic structure to the rutile one. These results not only explain the experimental observations of the monoclinic metallic state and the decoupled structural and electronic transitions of VO2, but also provide a useful understanding for the metal-insulator transition in other strongly correlated d electron systems.


2014 ◽  
Vol 16 (19) ◽  
pp. 8783-8786 ◽  
Author(s):  
Qiang Song ◽  
Weitao Gong ◽  
Guiling Ning ◽  
Hassan Mehdi ◽  
Guiqi Zhang ◽  
...  

A synergic effect of sodium on the metal–insulator transition temperature reduction of tungsten-doped vanadium dioxide is noted.


Author(s):  
Wentao Hu ◽  
Ke Yang ◽  
Xuan Wen ◽  
Hua Wu

Cobaltates have rich spin-states and diverse properties. Using spin-state pictures and first-principles calculations, we study the electronic structure and magnetism of the mixed-valent double perovskite YBaCo2O6. We find that YBaCo2O6...


The present work studies the microstructural and electrical properties of La0.9Pb0.1MnO3 and La0.8Y0.1Pb0.1MnO3 ceramics synthesized by solid-state route method. Microstructure and elemental analysis of both samples were carried out by field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) method, respectively. Phase analysis by X-ray diffraction (XRD) indicated formation of single phase distorted structure. The XRD data were further analyzed by Rietveld refinement technique. Raman analysis reveals that Y atom substitutes La site into the LPMO with shifting of phonon modes. The temperature variation of resistivity of undoped and Y-doped La0.9Pb0.1MnO3 samples have been investigated. The electrical resistivity as a function of temperature showed that all samples undergo an metal-insulator (M-I) transition having a peak at transition temperature TMI. Y-doping increases the resistivity and the metal-insulator transition temperature (TMI) shifts to lower temperature. The temperature-dependent resistivity for temperatures less than metal-insulator transition is explained in terms the quadratic temperature dependence and for T > TMI, thermally activated conduction (TAC) is appropriate. Variation of frequency dispersion in permittivity and loss pattern due to La-site substitution in LPMO was observed in the dielectric response curve.


2021 ◽  
Vol 317 ◽  
pp. 17-21
Author(s):  
Muhammad Syazwan Mohd Sabri ◽  
Nur Ain Athirah Che Apandi ◽  
Norazila Ibrahim

The electroresistance, ER effect of La0.85Ag0.15Mn1-xMoxO3 (x = 0.00 and 0.05) samples prepared using solid method are investigated. The increased of applied current from 5 mA to 10 mA does not change the metal-insulator transition temperature, TMI for both samples however decreased the resistivity in the temperature region of 50 K – 300 K. Both samples exhibit large ER effect at low temperature region. At TMI, the ER value is 75.5% (x =0) and decrease to 34.15% (x = 0.05). However, at 300 K, the value of ER increases to 57 % for Mo substituted sample, and the value decreases to 6.4% for the x =0 sample. The enhanced ER effect at 300 K may be due to the growth of conductive filaments under increased applied current. The increase of applied current may perturb the arrangement of magnetic inhomogeneity induced by Mo substitution, result in reduction of resistivity and lead to the observation of ER effect. These findings suggest potential application of La0.85Ag0.15Mn1-xMoxO3 (x = 0.05) in spintronic devices.


2019 ◽  
Vol 55 (1) ◽  
pp. 99-106
Author(s):  
Xiaofen Guan ◽  
Rongrong Ma ◽  
Guowei Zhou ◽  
Zhiyong Quan ◽  
G. A. Gehring ◽  
...  

2020 ◽  
Vol 46 (15) ◽  
pp. 23560-23566
Author(s):  
Angélica Marcílio de Souza ◽  
Rodrigo Cercena ◽  
Rodrigo da Costa Duarte ◽  
Sabrina Arcaro ◽  
Alexandre Gonçalves Dal Bó

Sign in / Sign up

Export Citation Format

Share Document