Bipolar magnetic semiconducting behavior in VNbRuAl

In recent decades, the behavior of SrTiO3 upon annealing in reducing conditions has been under intense academic scrutiny. Classically, its conductivity can be described using point defect chemistry and predicting n-type or p-type semiconducting behavior depending on oxygen activity. In contrast, many examples of metallic behavior induced by thermal reduction have recently appeared in the literature, challenging this established understanding. In this study, we aim to resolve this contradiction by demonstrating that an initially insulating, as-received SrTiO3 single crystal can indeed be reduced to a metallic state, and is even stable against room temperature reoxidation. However, once the sample has been oxidized at a high temperature, subsequent reduction can no longer be used to induce metallic behavior, but semiconducting behavior in agreement with the predictions of point defect chemistry is observed. Our results indicate that the dislocation-rich surface layer plays a decisive role and that its local chemical composition can be changed depending on annealing conditions. This reveals that the prediction of the macroscopic electronic properties of SrTiO3 is a highly complex task, and not only the current temperature and oxygen activity but also the redox history play an important role.

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Flux-induced semiconducting behavior of a quantum network

Physical Review B ◽

10.1103/physrevb.79.193309 ◽

2009 ◽

Vol 79 (19) ◽

Cited By ~ 19

Author(s):

Shreekantha Sil ◽

Santanu K. Maiti ◽

Arunava Chakrabarti

Keyword(s):

Quantum Network ◽

Semiconducting Behavior

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Some New Nickel 1,2-Dichalcogenolene Complexes as Single-component Semiconductors

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0509 ◽

2007 ◽

Vol 62 (5) ◽

pp. 679-684 ◽

Cited By ~ 5

Author(s):

George C. Papavassiliou ◽

George C. Anyfantis ◽

Barry R. Steele ◽

Aris Terzis ◽

...

Keyword(s):

Band Gap ◽

Single Component ◽

Semiconducting Behavior ◽

Gap Values

Abstract The complexes Ni(dmeds)(dmit), Ni(dmedt)(dmit), Ni(dpedt)(dsit), Ni(dpedt)(dmit), and Ni(dcdt)(dmit) (where dmeds is dimethylethylenediselenolate, dmedt is dimethylethylenedithiolate, dpedt is diphenylethylenedithiolate, dcdt is 1,2-bis-decylsulfanyl-ethene-1,2-dithiolate, dmit is 1,3-dithiol-2-thione-4,5-dithiolate, and dsit is 1,3-dithiol-2-thione-4,5-diselenolate) were prepared and characterized. The new complexes exhibit semiconducting behavior, with band gap values around 0.8 eV.

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Semiconducting behavior of niobium-doped titanium oxide in the amorphous state

Applied Physics Letters ◽

10.1063/1.3698389 ◽

2012 ◽

Vol 100 (14) ◽

pp. 142103 ◽

Cited By ~ 11

Author(s):

Kyung-Chul Ok ◽

Joseph Park ◽

Ju Ho Lee ◽

Byung Du Ahn ◽

Je Hun Lee ◽

...

Keyword(s):

Titanium Oxide ◽

Amorphous State ◽

Niobium Doped ◽

Semiconducting Behavior

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Nb Substitution Effects on Superconducting Properties ofRu1−xNbxSr2Eu1.4Ce0.6Cu2O10−δ

Advances in Condensed Matter Physics ◽

10.1155/2013/461652 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

J. L. Maldonado-Mejía ◽

J. D. Quiz-Celestino ◽

M. E. Botello-Zubiate ◽

S. A. Palomares-Sánchez ◽

J. A. Matutes-Aquino

Keyword(s):

Solid State Reaction Method ◽

Substitution Effects ◽

Superconducting Transition ◽

Metallic Behavior ◽

Resistivity Measurements ◽

Niobium Doping ◽

Method Substitution ◽

Insight Into ◽

Semiconducting Behavior

In order to gain further insight into the role of substitution of Ru by Nb on superconductivity, polycrystalline samples of Ru1−xNbxSr2Eu1.4Ce0.6Cu2O10−δ (0.0 ≤x≤ 1.0) have been synthesized by solid-state reaction method. Substitution of Nb at the Ru site in the system takes place isostructurally in the tetragonal structure (space groupI4/mmm) with full solubility (x= 1.0). Superconductivity exists for all compositions. Resistivity measurements in function of temperature from 0 to 300 K were done using the four-probe technique. It is found that the substitution of Ru5+for Nb5+depresses the superconductivity of samples fromTc = 29 K forx= 0.0 toTc = 5 K forx= 1.0 (whereTcis the critical temperature, when resistivity becomes equal to zero). In the normal state, the dependence of resistivity with temperature, for compositions withx = 0.0 and 0.2, shows a metallic behavior, while for compositions betweenx= 0.4 andx= 1 it shows a semiconducting behavior. In that way, the density of charge carriers is reduced with niobium doping, leading to the semiconducting behavior. The resistive transition to the superconducting state of all samples is found to be affected by granularity. Samples undergo double superconducting transition.

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Mn-induced Ferromagnetic Semiconducting Behavior with Linear Negative Magnetoresistance in Sr4(Ru1−xMnx)3O10 Single Crystals

Scientific Reports ◽

10.1038/s41598-018-31679-w ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Lingyi Xing ◽

Xin Gui ◽

Weiwei Xie ◽

Huibo Cao ◽

Jiaqiang Yan ◽

...

Keyword(s):

Single Crystals ◽

Negative Magnetoresistance ◽

Semiconducting Behavior

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Bipolar Conduction as the Possible Origin of the Electronic Transition in Pentatellurides: Metallic vs Semiconducting Behavior

Physical Review X ◽

10.1103/physrevx.8.021055 ◽

2018 ◽

Vol 8 (2) ◽

Cited By ~ 27

Author(s):

P. Shahi ◽

D. J. Singh ◽

J. P. Sun ◽

L. X. Zhao ◽

G. F. Chen ◽

...

Keyword(s):

Electronic Transition ◽

Bipolar Conduction ◽

Semiconducting Behavior

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Theoretical Analysis on Resistance-Temperature Characteristic of Ni/HCl-PANI Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.852.142 ◽

2014 ◽

Vol 852 ◽

pp. 142-146 ◽

Cited By ~ 2

Author(s):

Sui Yu Qiu ◽

Zhi Wei Yang ◽

Hong Qiu

Keyword(s):

Transition Temperature ◽

Theoretical Analysis ◽

Film Thickness ◽

Temperature Characteristic ◽

Substrate Thickness ◽

Upper Limit ◽

Metallic Conduction ◽

Conduction Behavior ◽

Doped Polyaniline ◽

Semiconducting Behavior

Ni/HCl-PANI composites were formed by depositing Ni films on HCl-doped polyaniline (HCl-PANI) substrates. A simple parallel resistor model is used to analyze the resistance-temperature (R-T) characteristic of the composite within 30-300 K. The theoretical analysis reveals that the composite exhibits a metal-semiconductor transition within a certain thickness of the Ni film or the HCl-PANI substrate. The composite shows a semiconducting behavior at temperatures over the transition temperature and a metallic conduction behavior at temperatures below the transition temperature. The transition temperature increases with increasing Ni film thickness whereas it decreases with increasing HCl-PANI substrate thickness. When the Ni film thickness exceeds its upper limit or the HCl-PANI substrate thickness is below its lower limit, the composite only shows the metallic R-T characteristic. When the HCl-PANI substrate thickness exceeds its upper limit, the composite only exhibits the semicoducting R-T characteristic.

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Thermoelectric Properties of Ru2Si3-Based Chimney-Ladder Phases

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.463 ◽

2007 ◽

Vol 561-565 ◽

pp. 463-466 ◽

Cited By ~ 4

Author(s):

Kyosuke Kishida ◽

Akira Ishida ◽

Katsushi Tanaka ◽

Haruyuki Inui

Keyword(s):

Crystal Structures ◽

Thermoelectric Properties ◽

Electron Concentration ◽

Valence Electron ◽

Valence Electron Concentration ◽

Compositional Range ◽

Wide Compositional Range ◽

P Type ◽

Semiconducting Behavior

The variations of the crystal structures and thermoelectric properties of the Ru1-xRexSiy chimney-ladder phases were studied as a function of the Re concentration. A series of chimney-ladder phases with a compositional formula of Ru1-xRexSi1.539+0.178x are formed in a wide compositional range, 0.14 ≤ x ≤ 0.76. The composition of the chimney-ladder phase is systematically deviated from the idealized composition satisfying the valence electron concentration rule: VEC=14. Measurements of thermoelectric properties reveal that the chimney-ladder phases exhibit n-type semiconducting behavior at low Re concentrations and p-type semiconducting behavior at high Re concentrations, which are well consistent with the prediction based on the deviation of the composition of the chimney-ladder phase from the idealized composition.

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