The surface metal-insulator phase transition of MBE (1 0 0) magnetite thin film

Vacuum ◽  
2001 ◽  
Vol 63 (1-2) ◽  
pp. 349-354 ◽  
Author(s):  
W Soszka ◽  
N.-T.H Kim-Ngan ◽  
D Sitko ◽  
G Jagło ◽  
J Korecki ◽  
...  
2000 ◽  
Vol 654 ◽  
Author(s):  
K. Dovidenko ◽  
S. Beasor ◽  
A. Topol ◽  
H. Efstathiadis ◽  
S. Oktyabrsky ◽  
...  

AbstractWe present the results of detailed chemical and structural characterization of the VO2/Al/Si(100) thin film heterostructures fabricated by chemical vapor deposition and physical vapor deposition methods. The presence of the thermochromic behavior in the VO2 layer around 68°C and its correlation with the layer composition and structure are discussed. The study compares the structural and chemical properties of the two types of thin VO2 layers: one which exhibits a metal-insulator phase transition around 68°C, and another which fails to undergo the temperature-induced transition. The study of interfaces was carried out by transmission electron microscopy, and showed the existence of an aluminum oxide interfacial layer between VO2 and Al for the samples with the metal-insulator phase transition. The smooth VO2/Al interface and the presence of more than one VO2 monoclinic polytypes were observed for the CVD films exhibiting no phase transition.


1983 ◽  
Vol 48 (5) ◽  
pp. 471-474 ◽  
Author(s):  
S Stizza ◽  
I Davoli ◽  
R Bernardini ◽  
A Bianconi ◽  
M Benfatto

Author(s):  
Yiheng Chen ◽  
Wen-Ti Guo ◽  
Zi-si Chen ◽  
Suyun Wang ◽  
Jian-Min Zhang

Abstract In recent years, the discovery of "magic angle" graphene has given new inspiration to the formation of heterojunctions. Similarly, the use of hexagonal boron nitride, known as white graphene, as a substrate for graphene devices has more aroused great interest in the graphene/hexagonal boron nitride (G/hBN) heterostructure system. Based on the first principles method of density functional theory, the band structure, density of states, Mulliken population, and differential charge density of a tightly packed model of twisted graphene/hexagonal boron nitride/graphene (G/hBN/G) sandwich structure have been studied. Through the establishment of heterostructure models TBG inserting hBN with different twisted angles, it was found that the band gap, Mulliken population, and charge density, exhibited specific evolution regulars with the rotation angle of the upper graphene, showing novel electronic properties and realizing metal-insulator phase transition. We find that the particular value of the twist angle at which the metal-insulator phase transition occurs and propose a rotational regulation mechanism with angular periodicity. Our results have guiding significance for the practical application of heterojunction electronic devices.


2013 ◽  
Vol 113 (17) ◽  
pp. 17A934 ◽  
Author(s):  
Tran Van Quang ◽  
Miyoung Kim

2002 ◽  
Vol 66 (4) ◽  
Author(s):  
E. V. Gorbar ◽  
V. P. Gusynin ◽  
V. A. Miransky ◽  
I. A. Shovkovy

2008 ◽  
Vol 77 (20) ◽  
Author(s):  
Canhua Liu ◽  
Takeshi Inaoka ◽  
Shin Yaginuma ◽  
Tomonobu Nakayama ◽  
Masakazu Aono ◽  
...  

2020 ◽  
Vol 2 (1) ◽  
pp. 37-42
Author(s):  
Arunachalam M ◽  
Thamilmaran P ◽  
Sakthipandi K

Lanthanum calcium based perovskites are found to be advantageous for the possible applications in magnetic sensors/reading heads, cathodes in solid oxide fuel cells, and frequency switching devices. In the present investigation La0.3Ca0.7MnO3 perovskites were synthesised through solid state reaction and sintered at four different temperatures such as 900, 1000, 1100 and 1200˚ C. X-ray powder diffraction pattern confirms that the prepared La0.3Ca0.7MnO3 perovskites have orthorhombic structure with Pnma space group. Ultrasonic in-situ measurements have been carried out on the La0.3Ca0.7MnO3 perovskites over wide range of temperature and elastic constants such as bulk modulus of the prepared La0.3Ca0.7MnO3 perovskites was obtained as function of temperature. The temperature-dependent bulk modulus has shown an interesting anomaly at the metal-insulator phase transition. The metal insulator transition temperature derived from temperature-dependent bulk modulus increases from temperature 352˚ C to 367˚ C with the increase of sintering temperature from 900 to 1200˚ C.


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