Normal-state transport in superconducting NbN films on r-cut sapphire

Abstract High-quality thin NbN films are very crucial for realizing quantum devices. Here, we investigated electrical transport and noise properties of a series of thin NbN films of various thicknesses grown on r-cut sapphire substrate using a DC magnetron sputtering technique. The films exhibit non-uniform thickness dependences for superconducting transition temperature (Te ) and normal-state resistivity. Morphological characterization of NbN samples of various thicknesses reveals uniform structure in thin films and granular structure in thick films. By measuring transport and noise properties in a normal state, we observe that the granular structure of NbN films does not have a strong effect on resistivity and does not cause an additional source of current noise.

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ELECTRICAL CHARACTERIZATION OF EPITAXIAL BI:2201

Modern Physics Letters B ◽

10.1142/s0217984902003567 ◽

2002 ◽

Vol 16 (04) ◽

pp. 127-133 ◽

Cited By ~ 1

Author(s):

A. V. POP ◽

G. ILONCA ◽

MARIANA POP ◽

R. DELTOUR

Keyword(s):

Thin Films ◽

Electrical Resistivity ◽

Magnetron Sputtering ◽

Normal State ◽

Electrical Resistance ◽

Electrical Characterization ◽

Dc Magnetron Sputtering ◽

Normal State Resistivity ◽

Partial Pressures

Bi2.1Sr1.9CuOy thin films (Bi:2201) were deposited onto heated single crystal (100) MgO substrates using inverted cylindrical DC magnetron sputtering with different partial pressures of oxygen in a sputtering gas. The behavior of the normal state resistivity function of temperature is strongly influenced by the composition of sputtering gas used in thin films synthesis. Near the transition to the superconducting state, electrical resistivity changes strongly from "metallic" to insulator (MI). The origin for the increase of electrical resistance was analyzed using some models for the localization of mobile carriers. A good linearity is obtained for ln R as a function of Tα for α = 1/10 and for R as a function of ln T. The last behavior agrees with the pinning and fragmentation of 1D stripes in CuO2 planes.

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PRODUCTION AND CHARACTERIZATION OF Ba2NdSbO6 COMPLEX PEROVSKITE AS A SUBSTRATE FOR YBa2Cu3O7-δ SUPERCONDUCTING FILMS

Modern Physics Letters B ◽

10.1142/s021798490601069x ◽

2006 ◽

Vol 20 (08) ◽

pp. 427-437 ◽

Cited By ~ 8

Author(s):

Q. MADUEÑO ◽

D. A. LANDÍNEZ TÉLLEZ ◽

J. ROA-ROJAS

Keyword(s):

Thin Films ◽

Chemical Elements ◽

Compositional Analysis ◽

Morphological Characterization ◽

Superconducting Thin Films ◽

Superconducting Transition ◽

X Ray Diffraction ◽

X Ray ◽

Excellent Candidate

We report systematic studies of Ba 2 NdSbO 6 as substrates for the production of YBa 2 Cu 3 O 7-δ superconducting thin films. Chemical stability and crystallographic coupling between Ba 2 NdSbO 6 and YBCO were examined by characterizing Ba 2 NdSbO 6- YBa 2 Cu 3 O 7-δ (0 to 100 vol.%) polycrystalline composites. X-ray diffraction experiments showed that Ba 2 NdSbO 6 belongs to the complex cubic perovskite family. Moreover, we determine that these materials are chemically stables, e.g. there is no chemical reaction at the interface, and the lattice parameters evidenced a matching ~ 2%. Morphological characterization of our samples was performed through scanning electron microscopy, which revealed the existence of separated grains of Ba 2 NdSbO 6 and YBa 2 Cu 3 O 7-δ. Compositional analysis of samples was performed by energy dispersive X-ray experiments, which showed the inexistence of impurities or undesired chemical elements. DC susceptibility measurements permitted us to determine that the presence of Ba 2 NdSbO 6 does not affect the critical temperature of the superconducting transition of YBa 2 Cu 3 O 7-δ. Our results evidenced that Ba 2 NdSbO 6 is an excellent candidate as a substrate for the fabrication of YBa 2 Cu 3 O 7-δ superconducting thin films.

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ANOMALOUS RE-ENTRANT SUPERCONDUCTIVITY IN Sr0.4K0.6BiO3: RECOVERY OF SUPERCONDUCTIVITY WITH ELECTRIC AND MAGNETIC FIELD

International Journal of Modern Physics B ◽

10.1142/s0217979202013900 ◽

2002 ◽

Vol 16 (20n22) ◽

pp. 3189-3192

Author(s):

D. C. KIM ◽

J. S. KIM ◽

A. N. BARANOV ◽

Y. W. PARK ◽

J. S. PSHIRKOV ◽

...

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Normal State ◽

Superconducting State ◽

Electrical Transport ◽

Transport Current ◽

Zero Magnetic Field ◽

Resistive Transition ◽

Normal State Resistivity ◽

Electric And Magnetic Field

Anomalous re-entrant superconducting-normal resistive transition was observed in Sr 0.4 K 0.6 BiO 3 superconductor i.e., normal – supernormal behavior as temperature is increased. Contrary to previously reported re-entrant resistive behaviors in other compounds, the re-entrant resistivity appearing at zero magnetic field in Sr 0.4 K 0.6 BiO 3 is suppressed to zero by applying an external magnetic field (H) or increasing the electrical transport current (I): an observation of a zero resistive superconducting state induced by H or I. Comparisons of the normal-state resistivity data in different samples indicate an important role that disorder in the junction barriers between superconducting grains might play on the observed re-entrant resistivity behavior. Possible physical origins of this anomalous phenomenon are discussed.

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Morphological Characterization of Mycobacteriophage R1

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051281 ◽

1974 ◽

Vol 32 ◽

pp. 254-255

Author(s):

B. L. Soloff ◽

T. A. Rado

Keyword(s):

Carbon Source ◽

Stationary Phase ◽

Growth Phase ◽

Minimal Medium ◽

Morphological Characterization ◽

Logarithmic Growth Phase ◽

Complete Lysis ◽

Lysogenic Culture ◽

Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

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Morphological Characterization of Rhinacanthus Species of Sri Lanka

Planta Medica ◽

10.1055/s-0030-1251769 ◽

2010 ◽

Vol 76 (05) ◽

Author(s):

APPR Amarasinghe ◽

RP Karunagoda ◽

DSA Wijesundara

Keyword(s):

Sri Lanka ◽

Morphological Characterization

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Density and morphological characterization of bacteria in integrated and exclusive production systems

Scientific Electronic Archives ◽

10.36560/13920201194 ◽

2020 ◽

Vol 13 (11) ◽

pp. 1

Author(s):

A. R. B. Zanco ◽

A. Ferreira ◽

G. C. M. Berber ◽

E. N. Gonzaga ◽

D. C. C. Sabino

Keyword(s):

Bacterial Community ◽

Rainy Season ◽

Production Systems ◽

Cropping System ◽

Morphological Characterization ◽

Native Forest ◽

Exclusive Production ◽

Colony Forming Units

The different integrated production systems can directly interfere with its bacterial community. The present study aimed to assess density, bacterial diversity and the influence of dry and rainy season in different integrated and an exclusive production system. The fallow and a native forest area was assessed to. Samples were collected in 2012 March and September. The isolation were carried out into Petri dishes containing DYGS medium. The number of colony forming units (CFU) was counted after 48 hours and. The bacterial density ranged between 106 and 107 CFU g-1 soil. The crop system affected the dynamics of the bacterial community only in the rainy season. The rainy season showed greater density of total bacteria when compared to the dry period regardless of the cropping system. The dendrograms with 80 % similarity showed thirteen and fourteen groups in the rainy and dry seasons. Isolates with the capacity to solubilize phosphate in vitro were obtained from all areas in the two seasons, but this feature has been prevalent in bacteria isolated during the rainy season

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Characterization of Antibacterial-Producing Endophytic Fungi of Syzygiumpolyanthum Leaves

Infectious Disorders - Drug Targets ◽

10.2174/1871526519666181226123541 ◽

2020 ◽

Vol 20 (4) ◽

pp. 448-454

Author(s):

Rahmita Burhamzah ◽

Gemini Alam ◽

Herlina Rante

Keyword(s):

Molecular Characterization ◽

Endophytic Fungi ◽

Morphological Characterization ◽

Test Method ◽

Analysis Method ◽

Nitrogen Base ◽

Rdna Genes ◽

Antibacterial Screening ◽

Planting Method

Background: Endophytic fungi live in plants’ tissue and can produce the same bioactive compounds as its host plant produces. Syzygiumpolyanthum leaves have known to be one of the antibacterial compound producers. Aim and Objective: This study aimed to characterize morphologically, microscopically, and molecularly the antibacterial-producing endophytic fungi of Syzygiumpolyanthum leaves. Methods: The isolation of endophytic fungi was done by fragment planting method on PDA medium. The antibacterial screening was performed using the antagonistic test as the first screening followed by the disc diffusion test method. The morphological characterization was based on isolate’s mycelia color, growth pattern, margin, and surface texture of the colony, while the microscopic characterization was based on its hyphae characteristics. The molecular characterization of the isolate was done by nitrogen base sequence analysis method on nucleotide constituent of ITS rDNA genes of the isolate. Results: The results found that isolate DF1 has antibacterial activity against E.coli, S.aureus, P.acne, and P.aeruginosa, with the greatest inhibition at 10% concentration of broth fermentation extract on S.aureus with a diameter of inhibition of 13.77 mm. Conclusion: Based on macroscopic, microscopic, and molecular characterization, DF1 isolate is similar to Ceriporialacerate.

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Microscopic Image Segmentation and Morphological Characterization of Novel Chitosan/Silica Nanoparticle/Nisin Films Using Antimicrobial Technique for Blueberry Preservation

Membranes ◽

10.3390/membranes11050303 ◽

2021 ◽

Vol 11 (5) ◽

pp. 303

Author(s):

Rokayya Sami ◽

Schahrazad Soltane ◽

Mahmoud Helal

Keyword(s):

Ph Value ◽

Silica Nanoparticle ◽

Morphological Characterization ◽

Aerobic Bacteria ◽

Nano Materials ◽

Elongation At Break ◽

Stable Suspension ◽

Average Size ◽

Material Ductility

In the current work, the characterization of novel chitosan/silica nanoparticle/nisin films with the addition of nisin as an antimicrobial technique for blueberry preservation during storage is investigated. Chitosan/Silica Nanoparticle/N (CH-SN-N) films presented a stable suspension as the surface loads (45.9 mV) and the distribution was considered broad (0.62). The result shows that the pH value was increased gradually with the addition of nisin to 4.12, while the turbidity was the highest at 0.39. The content of the insoluble matter and contact angle were the highest for the Chitosan/Silica Nanoparticle (CH-SN) film at 5.68%. The use of nano-materials in chitosan films decreased the material ductility, reduced the tensile strength and elongation-at-break of the membrane. The coated blueberries with Chitosan/Silica Nanoparticle/N films reported the lowest microbial contamination counts at 2.82 log CFU/g followed by Chitosan/Silica Nanoparticle at 3.73 and 3.58 log CFU/g for the aerobic bacteria, molds, and yeasts population, respectively. It was observed that (CH) film extracted 94 regions with an average size of 449.10, at the same time (CH-SN) film extracted 169 regions with an average size of 130.53. The (CH-SN-N) film presented the best result at 5.19%. It could be observed that the size of the total region of the fruit for the (CH) case was the smallest (1663 pixels), which implied that the fruit lost moisture content. As a conclusion, (CH-SN-N) film is recommended for blueberry preservation to prolong the shelf-life during storage.

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