HIGH PRESSURE STUDY OF NOVEL ELECTRONIC PROPERTIES IN Sr2Fe(W1-xMox)O6 NEAR METAL-INSULATOR TRANSITION

Electrical resistivities of double perovskite oxides Sr 2 Fe ( W 1-x Mo x) O 6 have been measured at high pressure and high magnetic field to elucidate the transport properties of these materials. It is found that the main mechanism of the transport in the semiconducting phase is variable range hopping conduction and the insulating properties are suppressed by high pressure to show a crossover to metallic state. The magnetoresistances of these oxides are revealed to decrease at high pressure above 1 GPa. Extremely large Grüneisen parameters are found near x = 0.2, where the metal-insulator transition occurs. The origin for these properties will be briefly discussed in connection with the phase diagram.

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Variable-range hopping conduction and metal–insulator transition in amorphous RexSi1−xthin films

Semiconductor Science and Technology ◽

10.1088/0268-1242/26/9/095001 ◽

2011 ◽

Vol 26 (9) ◽

pp. 095001 ◽

Cited By ~ 7

Author(s):

K G Lisunov ◽

H Vinzelberg ◽

E Arushanov ◽

J Schumann

Keyword(s):

Insulator Transition ◽

Hopping Conduction ◽

Variable Range Hopping ◽

Metal Insulator Transition ◽

Metal Insulator ◽

Variable Range ◽

Variable Range Hopping Conduction

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Anomalous low-temperature specific heat around the metal-insulator transition in ordered double-perovskite alloysSr2Fe(Mo1−yWy)O6(0<~y<~1)

Physical Review B ◽

10.1103/physrevb.68.144407 ◽

2003 ◽

Vol 68 (14) ◽

Cited By ~ 9

Author(s):

T. Okuda ◽

K.-I. Kobayashi ◽

Y. Tomioka ◽

Y. Tokura

Keyword(s):

Low Temperature ◽

Specific Heat ◽

Double Perovskite ◽

Insulator Transition ◽

Metal Insulator Transition ◽

Metal Insulator ◽

Low Temperature Specific Heat

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Identification of a monoclinic metallic state in VO2 from a modified first-principles approach

Modern Physics Letters B ◽

10.1142/s0217984919501483 ◽

2019 ◽

Vol 33 (12) ◽

pp. 1950148

Author(s):

Yongcheng Liang ◽

Ping Qin ◽

Zhiyong Liang ◽

Lizhen Zhang ◽

Xun Yuan ◽

...

Keyword(s):

First Principles ◽

Lattice Distortion ◽

Insulator Transition ◽

Metallic State ◽

Strongly Correlated ◽

Electron Systems ◽

First Principles Calculations ◽

Monoclinic Structure ◽

Metal Insulator Transition ◽

Metal Insulator

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.

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