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The photonic spin Hall effect (PSHE) is analogous to the electronic spin Hall effect, which has substantial potential for optoelectronic applications. However, PSHE-based devices are rarely studied, and manipulating the PSHE by charge current has remained elusive thus far. In this paper, we demonstrate current-induced switching of PSHE in the Ce1Dy2Al0.42Fe4.58O12 thin film capping with Pt electrodes, which is mediated by spin–orbit torques at the Pt/Ce1Dy2Al0.42Fe4.58O12 interface. The results show that the transverse beam shifts related to the PSHE can be reversed by applying a small order of magnitude charge current (∼108 A·m−2) to the Pt layer in opposite directions, which predicts low dissipation in our proposed heterostructure. In addition, by applying an in-plane magnetic field, the saturation beam shifts can be increased, which can significantly enhance the switching ratio. [ABSTRACT FROM AUTHOR]

Noncollinear antiferromagnet Weyl semimetal Mn3Sn has recently attracted great research interest. Although large anomalous Hall effect (AHE), anomalous Nernst effect (ANE), and magneto-optical effect have been observed in Mn3Sn, most studies are based on single crystals. So far, it is still challenging to grow high quality epitaxial Mn3Sn thin films with transport and optical properties comparable to their single crystal counterparts. Here, we report the structure and magneto-optical and transport properties of epitaxial Mn3Sn thin films fabricated by pulsed laser deposition (PLD). Highly oriented Mn3+xSn1−x (0001) and (11 2 ¯ 0) epitaxial films are growth on single crystalline Al2O3 and MgO substrates. Large anomalous Hall effect up to Δ ρ H = 3.02 μ Ω cm and longitudinal magneto-optical Kerr effect with |θK| = 38.1 mdeg at 633 nm wavelength are measured at 300 K, which are comparable to Mn3Sn single crystals. Our work demonstrates that high quality Mn3Sn epitaxial thin films can be fabricated by PLD, paving the way for future device applications. [ABSTRACT FROM AUTHOR]

Phase change materials, such as vanadium dioxide (VO2) and Titanium dioxide (Ti2O3) have received extensive attention because of the dramatic changes in their intrinsic properties during phase transitions. However, due to the rapid transition rate and wide dynamics, monitoring of processes is challenging. Previous detection methods are lack of speed and simplicity and require multiple interventions, which largely introduce human factors influencing the results and make it difficult to guarantee the accuracy and visualization. In this paper, the photonic spin Hall effect is used for real-time detection and highly sensitive analysis of the phase transition process of VO2 films. By incorporating with quantum weak measurement, the photonic spin-Hall shift acts as the pointer, and the phase transition process of VO2 is characterized effectively. The high measurement resolution with 63 S/(m μm) is achieved due to weak-value amplification. In our scheme, it does not involve any mechanical adjustment of optical components, thus enabling real-time, visual, non-contact detection of dynamic phase transition processes. [ABSTRACT FROM AUTHOR]

In this report, dysprosium substituted Ce1Y2Fe5O12 (Ce:YIG) thin films (Dy:CeYIG) with perpendicular magnetic anisotropy (PMA) are successfully deposited on silicon and silicon-on-insulator waveguides by pulsed laser deposition. The structural, magnetic, and magneto-optical properties of Dy:CeYIG films are investigated. We find that increasing dysprosium concentration leads to a decreased out-of-plane magnetic saturation field. Dy2Ce1Fe5O12 and Dy2Ce1Al0.4Fe4.6O12 thin films show PMA dominated by magnetoelastic effects due to thermal mismatch strain. These films further exhibit high Faraday rotation and low optical loss. Our work demonstrates that Dy substitution is an effective way to induce PMA in Ce:YIG thin films without compromising their magneto-optical figure of merit, making this material promising for self-biased transverse electric mode optical isolator applications. [ABSTRACT FROM AUTHOR]

Magnetic thin films with perpendicular magnetic anisotropy (PMA) offer opportunities for studying magnetostatic forward volume mode (MSFVM) spin waves with isotropic propagation. Here, we realize the full reciprocal MSFVM spin wave propagation in a 30-nm-thick manganese doped yttrium iron garnet (YIG) with PMA by only applying an external field of 5 mT. The external magnetic field required for investigating the MSFVM spin waves in YIG is reduced by 34 times compared to the in-plane magnetized one. The spin wave group velocity and decay length are also investigated. Our finding paves the way for applications of isotropic magnonic computing systems and logic devices. [ABSTRACT FROM AUTHOR]

Magnetically doped CeO2 is a promising dilute magnetic semiconductor and may also be useful in magneto-optical applications. Ce1-xCoxO2-δ (x=0, 0.02, 0.06, 0.15, and 0.25) films were deposited by pulsed laser deposition on MgO(100) substrates and their structural, magnetic, and magneto-optical properties were characterized. The films show a textured ceria single phase with (111) preferred orientation. All the Co-doped samples show room temperature ferromagnetism and large magnetic anisotropy with an out-of-plane easy axis. Magneto-optical measurements indicate that the Co-doped films also have high saturation Faraday rotation ranging from 230 to 6000 deg/cm depending on the Co concentration, and their refractive index and extinction coefficient also increase with Co concentration. [ABSTRACT FROM AUTHOR]

Magnetic garnets with Bi3+ are the standard media of discrete Faraday rotation isolators for IR-laser/fiber-optical transmission at 1.55 μm wavelength. For monolithic integration with semiconductors, perovskites of generic formula A[B]O3 offer promising alternatives that involve combinations of select transition-metal ions in octahedral B sites. In this paper, two concepts are described. In both cases, the 180° B–O–B bonding of the perovskite lattice could provide superexchange fields large enough to maintain spin ordering at room temperature. One model proposes a quasiferrite arrangement with antiferromagnetic alignment between Fe3+ and Ni2+ charge ordered in the double perovskite compound {A3+A′4+}[Fe3+Ni2+]O6. The other concept relies on ferromagnetism through delocalization superexchange with the composition A23+[Mn4+Ni2+]O6. Where appropriate to enhance Faraday rotation, Bi3+ can be used for A3+. [ABSTRACT FROM AUTHOR]

In this article, a systematic study on the magnetic properties and strain tunability of 3d transition metal ions (Mn, Fe, Co, Ni) doped MoS2 using first-principles calculations is performed. Antiferromagnetic coupling is observed between Mn, Fe ions and the nearest neighbor Mo ions; whereas ferromagnetic coupling is observed in Co and Ni systems. It is also shown that by applying biaxial tensile strain, a significant change of the magnetic moment is observed in all transition metal doped MoS2 materials with a strain threshold. The changes of total magnetic moment have different mechanisms for different doping systems including an abrupt change of the bond lengths, charge transfer and strain induced structural anisotropy. These results demonstrate applying strain as a promising method for tuning the magnetic properties in transition metal ion doped monolayer MoS2. [ABSTRACT FROM AUTHOR]

SrTi1-xFexO3 thin films were grown on Si substrates with a double buffer layer of ceria and yttria-stabilized zirconia at various temperatures, oxygen pressures and Fe contents. Films with in-plane compressive strain and an oxygen deficiency have a strong magnetic anisotropy with an out-of-plane easy axis, whereas films deposited at low temperature and in an oxygen atmosphere have no ferromagnetism at room temperature, which is attributed to the lack of lattice strain. [ABSTRACT FROM AUTHOR]

Measurements of Faraday rotation (FR) in [001]-oriented epitaxial films of SrTi1-xFexO3 and SrTi1-xCoxO3 with x = 0.4 and 0.3, respectively, indicate that FR constants (∼103 deg/cm) of these perovskite compounds can approach those of (Bi,Y)3Fe5O12 garnet used in fiber-optical isolators at a wavelength of 1.5 μm. Because the magnetic site in a stoichiometric host is occupied by Ti4+, substituted Fe or Co must also be 4+. A reduction to Fe3+, Fe2+, and Co3+, Co2+ is also expected from O2- loss during the deposition process. The orbital energy-level structures in an octahedral site are examined for the existence of transitions that could account for the similar high FR effects. It was determined that only Fe4+ and Co4+ in low-spin states can satisfy the selection rules. The observation that the respective coercive fields of the FR(H) hysteresis loops exceed those of the magnetic moment M(H) lends credence to the argument that the unquenched orbital angular momentum acting with spin-orbit coupling can become the dominating influence on collective magnetic alignment. [ABSTRACT FROM AUTHOR]

Graphene is a promising THz magneto-optical material. However, high Faraday rotation is only achievable at a low THz frequency range in single layer graphene. In this paper, we report simultaneous Faraday rotation and optical transmission enhancement in Au grating/graphene/silicon hybrid plasmonic structures across a wide frequency range from 0.43 to 24 THz using extraordinary transmission of THz spoof surface plasmons. In a broad frequency range up to 13.1 THz, the Faraday rotation and magneto-optical figure of merit in this hybrid structure can exceed the maximum value of single layer graphene at the low THz frequency range. Numerical analysis on the device dispersion relation indicates that the mechanism of simultaneous Faraday rotation and transmission enhancement is due to coupling of the TE waveguide mode with the TM hybrid waveguide-plasmon mode. Our work demonstrates the hybrid plasmonic structure as a promising candidate for THz nonreciprocal photonic device applications. [ABSTRACT FROM AUTHOR]

We have determined the effective work function ([uppercase_phi_synonym]m,eff) of thin-film sputter-deposited Pr0.7Ca0.3MnO3 (PCMO) on atomic-layer-deposited ZrOx. Pt/PCMO/ZrOx/SiO2/Si and Pt/ZrOx/SiO2/Si metal-oxide-semiconductor (MOS) capacitors were fabricated. The [uppercase_phi_synonym]m,eff were extracted from capacitance-voltage curves of the MOS capacitors by using flat-band voltage versus effective-oxide-thickness plots. PCMO was crystallized using a high-temperature anneal step and crystallinity was confirmed by x-ray diffraction and transmission electron microscopy. [uppercase_phi_synonym]m,eff of polycrystalline PCMO and Pt on ZrOx was determined to be 5.43 eV and 5.40 eV, respectively. The significantly higher [uppercase_phi_synonym]m,eff of PCMO is attributed to the presence of oxygen-rich PCMO(002)/ZrOx interfaces as indicated by our density-functional-theory calculations. [ABSTRACT FROM AUTHOR]

A path integral Monte Carlo method based on the fast-Fourier transform technique combined with the important sampling method is proposed to calculate the decay rate of a metastable quantum system with an arbitrary shape of a potential barrier. The contribution of all fluctuation actions is included which can be used to check the accuracy of the usual steepest-descent approximation, namely, the perturbation expansion of potential. The analytical approximation is found to produce the decay rate of a particle in a cubic potential being about 20% larger than the Monte Carlo data at the crossover temperature. This disagreement increases with increasing complexity of the potential shape. We also demonstrate via Langevin simulation that the postsaddle potential influences strongly upon the classical escape rate.