Vortex imaging in superconducting films by Scanning Hall Probe Microscopy

Oral, Ahmet
We have used a low noise Scanning Hall Probe Microscope (SHPM) to study vortex structures in superconducting films. The microscope has high magnetic field (similar to 2.9 x 10(-8)T/root Hz at 77 K) and spatial resolution, similar to 0.85 mu m. Magnetic field profiles of single vortices in High T-c YBa2Cu3O7-delta thin films have been successfully measured and the microscopic penetration depth of the superconductor has been extracted as a function of temperature. Flux penetration into the superconductor has been imaged in real time (similar to 8s/frame).


Dispersive optical constants of Tl2InGaSe4 single crystals
Qasrawi, A. F.; Hasanlı, Nızamı (IOP Publishing, 2007-09-01)
The structural and optical properties of Bridgman method grown Tl2InGaSe4 crystals have been investigated by means of room temperature x-ray diffraction, and transmittance and reflectance spectral analysis, respectively. The x-ray diffraction technique has shown that Tl2InGaSe4 is a single phase crystal of a monoclinic unit cell that exhibits the lattice parameters of a = 0.77244 nm, b = 0.64945 nm, c = 0.92205 nm and beta = 95.03 degrees . The optical data have revealed an indirect allowed transition band ...
Thermal lattice scattering mobility and carrier effective mass in intrinsic Tl2InGaTe4 single crystals
Qasrawi, A. F.; Hasanlı, Nızamı (IOP Publishing, 2007-04-18)
Systematic structural, dark electrical resistivity and Hall coefficient measurements have been carried out on n- type Tl2InGaTe4 single crystals. The data from x- ray powder diffraction allowed determination of the tetragonal unit cell lattice parameters. Analysis of the electrical resistivity and carrier concentration, which was recorded in the temperature range 210 - 350 K, reveals the intrinsic type of conduction with an average energy band gap of 0.85 eV. The temperature- dependent Hall mobility was obs...
Object reconstruction from in-line Fresnel holograms without explicit depth focusing
Ozgen, MT; Tuncer, Temel Engin (SPIE-Intl Soc Optical Eng, 2004-06-01)
We propose two computational techniques for extracting object cross-sectional shape information from digitized in-line Fresnel holograms that do not require prior knowledge of object depths but recover relative depth information along the way. The first algorithm is applicable to hologram segments involving a single particle only. It is based on estimating Fourier transform magnitude and phase of the particle from those of the hologram segment. The second algorithm conducts a joint inverse filtering and dep...
Absorption edge and optical constants of layered structured Tl2Ga2Se3S single crystals
Hasanlı, Nızamı (IOP Publishing, 2012-06-01)
The optical properties of Tl2Ga2Se3S layered crystals have been studied through transmission and reflection measurements in the photon energy range 1.13-2.82 eV. The optical indirect and direct transitions with band gap energies of 2.15 and 2.54 eV, respectively, were determined from the analysis of absorption data at room temperature. The dispersion of refractive index is discussed in terms of the Wemple-DiDomenico single-effective oscillator model. The refractive index dispersion parameters, namely oscill...
Nonlinear optical properties of a Woods-Saxon quantum dot under an electric field
AYTEKİN, ÖZLEM; Turgut, Sadi; Unal, V. Ustoglu; Aksahin, E.; Tomak, Mehmet (Elsevier BV, 2013-12-01)
A theoretical study of the effect of the confining potential on the nonlinear optical properties of two dimensional quantum dots is performed. A three-parameter Woods-Saxon potential is used within the density matrix formalism. The control of confinement by three parameters and an applied electric field gives one quite an advantage in studying their effects on the nonlinear properties. The coefficients investigated include the optical rectification, second and third-harmonic generation and the change in the...
Citation Formats
A. Oral, R. G. HUMPHREYS, and M. HENİNİ, “Vortex imaging in superconducting films by Scanning Hall Probe Microscopy,” JOURNAL OF LOW TEMPERATURE PHYSICS, pp. 1135–1140, 1996, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46615.