All-optical control of ferromagnetic thin films and nanostructures: Competition between polarized light and applied magnetic field

The non-resonant microwave absorption (NRMA) measurements have been intensively performed for superconducting thin films of YBa 2 Cu 3 O y fabricated on MgO (100) substrates and powder samples of LaSrCuO systems. In order to complement the study, we also review the NRMA of BiSrCaCuO system. A particular attention has been paid to the following phenomena: (i) phases, (ii) effect of current, (iii) directional effect of applied magnetic field, (iv) hysteresis, (v) microwave power absorbed as a function of magnetic field, (vi) linewidth in the vicinity of T c , and (vii) modulation amplitude effect. A preliminary study on ( La 0.98 Dy 0.02)1.85 Sr 0.15 CuO 4 was also reported.

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Upper Critical Field and Irreversibility Line in Bi2Sr2CuO6+δ/CaCuO2 Superconducting Superlattices Obtained by MBE

International Journal of Modern Physics B ◽

10.1142/s0217979200002879 ◽

2000 ◽

Vol 14 (25n27) ◽

pp. 2767-2772

Author(s):

Matteo Salvato ◽

Carmine Attanasio ◽

Gerardina Carbone ◽

Rosalba Fittipaldi ◽

Tiziana Di Luccio ◽

...

Keyword(s):

Magnetic Field ◽

Experimental Data ◽

Thin Films ◽

Phase Diagrams ◽

Applied Magnetic Field ◽

Three Dimensional ◽

Upper Critical Field ◽

Resistivity Measurements ◽

T Phase ◽

The Magnetic Field

Resistivity measurements in external applied magnetic field up to 8.5T have been performed on Bi2Sr2CuO6+δ/CaCuO2 superconducting superlattices obtained by MBE. The magnetic field (H) vs. temperature (T) phase diagrams have been determined and the experimental data have been compared with that obtained in the case of Bi2Sr2CuO6+δ thin films deposited with the same technique. A reduction of the anisotropy has been obtained in the case of the superlattices with respect to the case of Bi2Sr2CuO6+δ thin films and a three dimensional behavior has been observed by paraconductivity measurements.

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nanoSQUID operation using kinetic rather than magnetic induction

Scientific Reports ◽

10.1038/srep28095 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 9

Author(s):

Adam N. McCaughan ◽

Qingyuan Zhao ◽

Karl K. Berggren

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Applied Magnetic Field ◽

Magnetic Induction ◽

Quantization Condition ◽

Kinetic Inductance ◽

Superconducting Thin Films ◽

Magnetic Inductance ◽

Measurement Results ◽

Superconducting Loop

Abstract We report on a method of nanoSQUID modulation which uses kinetic inductance rather than magnetic inductance to manip-ulate the internal fluxoid state. We produced modulation using injected current rather than an applied magnetic field. Using this injected current, we were able to observe the triangle-wave shaped modulation of the device critical current which was periodic according to the London fluxoid quantization condition. The measurement results also confirmed that the fluxoid state inside a superconducting loop can be manipulated using primarily kinetic inductance. By using primarily kinetic inductance rather than magnetic inductance, the size of the coupling inductor was reduced by a factor of 10. As a result, this approach may provide a means to reduce the size of SQUID-based superconducting electronics. Additionally, this method provides a convenient way to perform kinetic inductance characterizations of superconducting thin films.

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Voltage noise behavior in highly textured YBa2Cu3O7-δ thin films under the applied magnetic field

Physica C Superconductivity ◽

10.1016/s0921-4534(00)01126-6 ◽

2000 ◽

Vol 341-348 ◽

pp. 1223-1224

Author(s):

A. Taoufik ◽

A. Tirbiyine ◽

S. Senoussi ◽

A. Ramzi

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Applied Magnetic Field ◽

Voltage Noise

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The role of applied magnetic field in Co-doped ZnS thin films fabricated by pulsed laser deposition

Optical Materials ◽

10.1016/j.optmat.2021.110877 ◽

2021 ◽

Vol 114 ◽

pp. 110877

Author(s):

Dongwen Gao ◽

Li Wang ◽

Xueqiong Su ◽

Jin Wang ◽

Ruixiang Chen

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Pulsed Laser Deposition ◽

Applied Magnetic Field ◽

Pulsed Laser ◽

Laser Deposition ◽

Co Doped

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Optical Transition Rates in a Cylindrical Quantum Wire with Parabolic and Inverse Parabolic Electric Confining Potentials in a Magnetic Field

10.21203/rs.3.rs-573174/v1 ◽

2021 ◽

Author(s):

Moletlanyi Tshipa ◽

Monkami Masale

Keyword(s):

Magnetic Field ◽

Applied Magnetic Field ◽

Polarized Light ◽

Electronic States ◽

Dipole Approximation ◽

Transition Rates ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Quantum Numbers ◽

Parabolic Potential

Abstract Electron transition rates due to interaction with circularly polarized light incident along the axis of a free-standing solid cylindrical nanowire are evaluated in the dipole approximation. The electric confinement potential of the nanowire is modeled as a superposition of two parts, in general, of different strengths; viz; parabolic and inverse parabolic in the radial distance. Additional confinement of the charge carriers is through the vector potential of the axial applied magnetic field. In systems with cylindrical symmetry, the electronic states are in part characterized by azimuthal quantum numbers: m=0, ±1, ±2,..., which in the absence of the axial applied magnetic field are doubly degenerate. In the dipole approximation and for circularly polarized light the selection rules are such that optical transitions are allowed between electronic states whose azimuthal quantum numbers differ by unity. Transition rates are characterized by peaks whenever the energy of the incident electromagnetic radiation matches transition energies for states between which transitions occur. The parabolic potential blue shifts peak of transition rates while the inverse parabolic potential redshifts the peaks. Results also indicate that transition rates are higher in nanowires of smaller radii. The homogeneous magnetic field lifts the double-degeneracies of electrons with opposite angular momenta, which leads to the emergence of two branches of the transition rates.

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Magneto-optics

Properties of Materials ◽

10.1093/oso/9780198520757.003.0033 ◽

2004 ◽

Author(s):

Robert E. Newnham

Keyword(s):

Magnetic Field ◽

Applied Magnetic Field ◽

Faraday Effect ◽

Magnetic Circular Dichroism ◽

Polarized Light ◽

Practical Interest ◽

Electronic Energy ◽

Kerr Rotation ◽

Linearly Polarized ◽

Magneto Optic

The magneto-optic properties of interest are the Faraday Effect, Kerr Rotation, and the Cotton–Mouton Effect. In 1846, Michael Faraday discovered that when linearly polarized light passes through glass in the presence of a magnetic field, the plane of polarization is rotated. The Faraday Effect is now used in a variety of microwave and optical devices. Normally the Faraday experiment is carried out in transmission, but rotation also occurs in reflection, the so-called Kerr Rotation that is used in magneto-optic disks with Mbit storage capability. Other magneto-optic phenomena of less practical interest include the Cotton– Mouton Effect, a quadratic relationship between birefringence and magnetic field, and magnetic circular dichroism that is closely related to the Faraday Effect. A number of nonlinear optical effects of magnetic or magnetoelectric origin are also under study. Almost all these magnetooptical effects are caused by the splitting of electronic energy levels by a magnetic field. This splitting was first discovered by the Dutch physicist Zeeman in 1896, and is referred to as the Zeeman Effect. When linearly polarized light travels parallel to a magnetic field, the plane of polarization is rotated through an angle ψ. It is found that the angle of rotation is given by . . . ψ(ω) = V(ω)Ht, . . . where H is the applied magnetic field, t is the sample thickness, ω is the angular frequency of the electromagnetic wave, and V(ω) is the Verdet coefficient. Faraday rotation is observed in nonmagnetic materials as well as in ferromagnets. The Verdet coefficient of a commercial one-way glass is plotted as a function of wavelength in Fig. 31.1(a). Corning 8363 is a rare earth borate glass developed to remove reflections from optical systems. A polarized laser beam is transmitted through the glass parallel to the applied magnetic field. The plane of polarization is rotated 45◦ by the Faraday Effect. The transmitted beam passes through the analyzer that is set at 45◦ to the polarizer. But the reflected waves coming from the surface of the glass and from the analyzer are rotated another 45◦ as they return toward the laser.

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Micromagnetic Modeling of All Optical Switching of Ferromagnetic Thin Films: The Role of Inverse Faraday Effect and Magnetic Circular Dichroism

Applied Sciences ◽

10.3390/app10041307 ◽

2020 ◽

Vol 10 (4) ◽

pp. 1307 ◽

Cited By ~ 2

Author(s):

Victor Raposo ◽

Rodrigo Guedas ◽

Felipe García-Sánchez ◽

M. Auxiliadora Hernández ◽

Marcelino Zazo ◽

...

Keyword(s):

Thin Films ◽

Optical Switching ◽

Faraday Effect ◽

Magnetic Circular Dichroism ◽

Laser Pulses ◽

Inverse Faraday Effect ◽

Ferromagnetic Thin Films ◽

All Optical ◽

Circular Dichroïsm ◽

All Optical Switching

There is a lot of experimental evidence of All Optical Switching (AOS) by applying ultrashort laser pulses on ferromagnetic thin films with perpendicular magnetic anisotropy. However, the physical origin behind these processes remains under debate. In addition to the heating caused by the laser pulses, the Inverse Faraday Effect (IFE) and Magnetic Circular Dichroism (MCD) have been proposed as the most probable phenomena responsible for the observations of helicity-dependent AOS. Here, we review the influence of both phenomena by means of realistic micromagnetic simulations based on the Landau–Lifshitz–Bloch equation coupled to the heat transport caused by the laser heating. The analysis allows us to reveal the similarities and differences between both effects. While both mechanisms may lead to the local inversion of the initial magnetic state of a ferromagnetic sample submitted to a train of circularly polarized laser pulses, the Inverse Faraday Effect proves to be more efficient for nucleation and domain wall movement and it reproduces more accurately the different magnetic configurations that the experiments report for different values of the fluence of the laser beam.

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