Transport Properties of Granular Nix(SiO2)100−x Thin Films

1990 ◽  
Vol 195 ◽  
Author(s):  
John R. Beamish ◽  
B.M. Patterson ◽  
K.M. Unruh
Keyword(s):  
Thin Films ◽  
Temperature Dependence ◽  
Electrical Transport ◽  
Low Temperatures ◽  
Room Temperature ◽  
Volume Percent ◽  
Ni Content ◽  
Resistivity Minimum ◽  
Temperature Coefficient Of Resistivity ◽  
Sputter Deposited

ABSTRACTWe have studied the electrical transport behavior of sputter deposited Nix(SiO2)100−x thin films between room temperature and 100 mK and, at selected temperatures, in applied magnetic fields up to 6 T. As the Ni concentration x is reduced, the resistivity increases systematically. At a Ni concentration (nominal) of about x–70 atomic percent (38 volume percent) the room temperature coefficient of resistivity changes sign. For Ni concentrations greater than 70 percent the resistance first decreases with temperature then increases logarithmically at, low temperatures. This increase becomes smaller and the resistivity minimum moves to progressively lower temperatures as the Ni concentration increases. In films with less than x–70 percent Ni, the resistivity has a temperature dependence of the form ρ(T)–ρo exp \(To/T)α] between room temperature and about 5 K. The exponent a is about 1/2 and To increases with decreasing Ni content. Below 1 K, however, the resistivity increases much less rapidly, with a temperature dependence independent of Ni concentration. In all films the magnetoresistance is small and negative.

scholarly journals Synthesis and Physical Properties of Antiperovskite CuNFe3 Thin Films via Solution Processing for Room Temperature Soft-Magnets

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 270
Author(s):  
Zhenzhen Hui ◽  
Qi Zhu ◽  
Chuan Liu ◽  
Jumeng Wei ◽  
Jing Tang ◽  
...  
Keyword(s):  
Thin Films ◽  
Physical Properties ◽  
Electrical Transport ◽  
Room Temperature ◽  
Electron Interaction ◽  
Solution Deposition ◽  
Soft Magnets ◽  
Solution Methods ◽  
Temperature Coefficient Of Resistivity ◽  
First Time

Antiperovskite CuNFe3 (CNF) thin films have been successfully prepared by chemical solution deposition (CSD) for the first time. They are versatile in many applications as an iron-based nitride. The preparation of pure CNF thin films is a challenging work for the complexity of the phase diagram. Herein, the CNF thin films are phase-pure and polycrystalline. Annealing temperature effects on the microstructures and physical properties were investigated, showing that the CNF thin films are metallic and can be considered as a candidate for room temperature soft-magnets with a large saturated magnetization (Ms) and a low coercive field (Hc). At high temperatures, the electrical transport behavior of CNF thin films presents a low temperature coefficient of resistivity (TCR) value, while the electron–electron interaction is prominent at low temperatures. The reported solution methods of CNF thin films will enable extensive fundamental investigation of the microstructures and properties as well as provide an effective route to prepare other antiperovskite transition-metal nitride thin films.

Temperature Dependence of the Electrical Conductivity of Poly(Benzo[1,2-b:4,5-b'] Dithiophene-4,8-Diyl Vinylene) and Poly(Dodecylthiophene)

1997 ◽  
Vol 488 ◽  
Author(s):  
R. C Hyer ◽  
R. G. Pethe ◽  
T. Yogi ◽  
S. C. Sharma ◽  
J. Wang ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Temperature Dependence ◽  
Low Temperatures ◽  
Room Temperature ◽  
Thermal Fluctuation ◽  
Variable Range Hopping ◽  
Tunneling Model ◽  
Three Samples ◽  
Electrical Conductivities

AbstractWe present results for the electrical conductivity (σ) of thin films of poly(benzo[1,2-b:4,5- b']dithiophene-4,8-diyl vinylene) (PBDV) and poly (dodecylthiophene) (PDDT) as a function of temperature in the range 15-295K. The polymers were doped with FeC13 and PF6 which resulted in electrical conductivities differing by two orders of magnitude at room temperature. We examine three sets of σ(T)-data by using the variable-range hopping (VRH) model that predicts a linear relationship between ln(T1/2σ) and T1/4. We observe a change in the slope of the ln(T1/2σ) vs T14 relationship in all three samples at low temperatures. We also analyze the temperature dependence of the resistivity of PBDV by using the thermal fluctuation-induced tunneling model.

Temperature dependence of electrical transport properties of La4BaCu5−xCoxO13+δconducting oxide thin films

2016 ◽  
Vol 55 (4S) ◽  
pp. 04EJ08
Author(s):  
Akihiro Tsuruta ◽  
Yusuke Tsujioka ◽  
Yutaka Yoshida ◽  
Ichiro Terasaki ◽  
Norimitsu Murayama ◽  
...  
Keyword(s):  
Thin Films ◽  
Temperature Dependence ◽  
Transport Properties ◽  
Electrical Transport ◽  
Oxide Thin Films ◽  
Electrical Transport Properties

Anomaly of Nuclear Quadrupole Relaxation in Cu2O Prepared at Low Temperatures

1986 ◽  
Vol 41 (1-2) ◽  
pp. 382-385 ◽  
Author(s):  
J. Kasprzak ◽  
J. Lus ◽  
J. Pietrzak
Keyword(s):  
Temperature Dependence ◽  
Cuprous Oxide ◽  
Thermal Processing ◽  
Low Temperatures ◽  
Room Temperature ◽  
Quadrupole Relaxation ◽  
Temperature Dependences ◽  
Powder Samples ◽  
Nuclear Quadrupole ◽  
Nuclear Quadrupole Relaxation

The 63Cu and 65Cu NQR transitions in powder samples of cuprous oxide have been investigated from 77 to 500 K and at room temperature after annealing up to 1100 K Significant differences in T1 , NQR linewidth Δv, and their temperature dependences were found among the samples prepared in different ways. For C u20 samples obtained in low temperatures (below 380 K), the temperature dependence of T1 below 380 K is o f activation character with Ea = 0.07 eV. These results are interpreted in terms of an electron hopping mechanism. Thermal processing of these samples permits to obtain irreversible electronic state and then the spectroscopic parameters are the same as for the samples obtained in high temperatures (above 1320 K).

Magnetic Penetration Depth Measurements and Inhomogeneity in YBa2Cu3O7−δ Superconducting Thin Films

1990 ◽  
Vol 195 ◽  
Author(s):  
Steven M. Anlage ◽  
Brian W. Langley ◽  
Jurgen Halbritter ◽  
Chang-Beom Eom ◽  
Neil Switz ◽  
...  
Keyword(s):  
Thin Films ◽  
Temperature Dependence ◽  
Penetration Depth ◽  
Exponential Decay ◽  
Power Law ◽  
Low Temperatures ◽  
Bcs Theory ◽  
Magnetic Penetration Depth ◽  
Microstrip Resonator ◽  
Magnetic Penetration

ABSTRACTThe microstrip resonator technique has been applied to study the temperature dependence of the magnetic penetration depth in high quality YBa2Cu3O7−δ thin films. The temperature dependence at low temperatures comes out directly from measured data, with no assumptions about transmission line geometry, dielectric properties, or a model for the temperature dependence of the penetration depth. One can interpret the data in terms of either an exponential decay of λ(T) at low temperatures or as a power law decay. The energy gaps obtained from the exponential decay at low temperature are found to be significantly smaller than weak coupled BCS theory and power-law exponents are in the range of 1.3 to 3.2. These results will be discussed in terms of microscopic theories and the possibility that materials properties dominate the measurement.

Electrical Transport and In-Situ X-Ray Studies of the Formation of TiSi2 Thin Films on Si

1986 ◽  
Vol 77 ◽  
Author(s):  
J. C. Hensel ◽  
J. M. Vandenberg ◽  
L. F. Mattheiss ◽  
F. C. Unterwald ◽  
A. Maury
Keyword(s):  
Thin Films ◽  
Electrical Transport ◽  
Structural Phase ◽  
X Ray Diffraction ◽  
Metallic Behavior ◽  
Distinctive Features ◽  
X Ray ◽  
Total Energies ◽  
Sputter Deposited

ABSTRACTThe formation of TiSi2 thin films on Si has been investigated by in situ x-ray diffraction and by electrical transport. The x-ray results show unequivocally that the staging proceeds through two orthorhombic polytypes of TiSi2 according to the sequence: sputter-deposited metallic Ti films on Si (001) → TiSi2 (C49 structure) → TiSi2 (C54 structure), with no evidence of lower suicides. Electrical transport shows metallic behavior for all phases and distinctive features in the annealing curves which correlate with the structural transformations. Most importantly, the resistivity, characteristically very high for the C49 phase, undergoes a precipitous drop at the C49 → C54 transition. Total energies for both phases are calculated and, consistent with the occurrence of a structural phase transformation, are found not to differ appreciably.

Transport Studies in Single-Crystal Films of Cosi2 and Nisi2

1983 ◽  
Vol 25 ◽  
Author(s):  
J. C. Hensel ◽  
R. T. Tung ◽  
J. M. Poate ◽  
F. C. Unterwald ◽  
D. C. Jacobson
Keyword(s):  
Thin Films ◽  
Single Crystal ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Room Temperature Resistivity ◽  
Transport Studies ◽  
Single Crystal Films ◽  
Crystal Films ◽  
The Difference ◽  
Temperature Resistivity

ABSTRACTTransport studies have been performed on thin films of CoSi 2 and NiSis2 in the temperature range 1 to 300 K. The conductivities are metallic with essentially the same temperature dependence; however, the residual resistivities are markedly different even though the two silicides are structurally similar (the room temperature resistivity of NiSi2 being at least twice that of CoSi2 of 15 μΩ cm). The difference is attributed to intrinsic defects in NiSi2. This defect has been simulated by ion bombardment of the film where it is also shown that Matthiesen's rule is obeyed over a remarkable range of bombardment doses.

Dielectric Properties of Pulsed Excimer Laser Ablated BaBi2Nb2O9 Thin Films

2002 ◽  
Vol 748 ◽  
Author(s):  
Apurba Laha ◽  
S. B. Krupanidhi ◽  
S. Saha
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Dielectric Constant ◽  
Temperature Dependence ◽  
Loss Tangent ◽  
Dielectric Response ◽  
Room Temperature ◽  
Dielectric Constant And Loss ◽  
Wide Range ◽  
Room Temperature Dielectric Constant

ABSTRACTThe dielectric response of BaBi2Nb2O9 (BBN) thin films has been studied as a function of frequency over a wide range of temperatures. Both dielectric constant and loss tangent of BBN thin films showed a ‘power law’ dependence with frequency, which was analyzed using the Jonscher's universal dielectric response model. Theoretical fits were utilized to compare the experimental results and also to estimate the value of temperature dependence parameters such as n(T) and a(T) used in the Jonscher's model. The room temperature dielectric constant (ε') of the BBN thin films was 214 with a loss tangent (tanδ) of 0.04 at a frequency of 100 kHz. The films exhibited the second order dielectric phase transition from ferroelectric to paraelectric state at a temperature of 220 °C. The nature of phase transition was confirmed from the temperature dependence of dielectric constant and sponteneous polarization,respectively. The calculated Currie constant for BBN thin films was 4 × 105°C.

SYNTHESIS AND CHARACTERIZATION OF COMPLEX FERROELECTRIC OXIDE

2012 ◽  
Vol 02 (04) ◽  
pp. 1250024 ◽  
Author(s):  
PIYUSH R. DAS ◽  
B. N. PARIDA ◽  
R. PADHEE ◽  
R. N. P. CHOUDHARY
Keyword(s):  
Temperature Dependence ◽  
Electrical Transport ◽  
Room Temperature ◽  
Structural Characteristics ◽  
Ferroelectric Properties ◽  
Complex Impedance ◽  
Electrical Transport Properties ◽  
Arrhenius Behavior ◽  
Orthorhombic Crystal ◽  
Grain Distribution

The polycrystalline sample of Li2Pb2Pr2W2Ti4V4O30 was prepared by a solid-state reaction technique. The preparation conditions of the compound have been optimized using thermal analysis (DTA and TGA) technique. Room temperature structural analysis confirms the formation of single phase compound in orthorhombic crystal system. The surface morphology of the sample, recorded by scanning electron microscope, shows uniform grain distribution on the surface of the sample. The observation of hysteresis loop confirmed that the material has ferroelectric properties at room temperature. Electrical properties of the material were studied by complex impedance spectroscopic technique. Temperature dependence of electrical parameters (impedance, modulus, etc.) is strongly correlated to the micro-structural characteristics (bulk, grain boundary, etc.) of the sample. A typical temperature-dependent resistive characteristic of the sample (i.e., negative temperature coefficient of resistance (NTCR)) exhibits its semiconducting properties. The temperature dependence of dc conductivity shows a typical Arrhenius behavior. A signature of ionic conductivity in the system was observed in ac conductivity spectrum. The sample obeys Jonscher's universal power law. The hopping mechanism for electrical transport properties of the system with nonexponential-type conductivity relaxation was suggested from the electrical modulus analysis.

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