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We synthesized a CaZrO3/SrTiO3 oxide heterostructure, which can serve as an alternative to LaAlO3/SrTiO3, and confirmed the generation of 2-dimensional electron gas (2-DEG) at the heterointerface. We analyzed the electrical-transport properties of the 2-DEG to elucidate its intrinsic characteristics. Based on the magnetic field dependence of resistance at 2 K, which exhibited Weak Anti-localization (WAL) behaviors, the fitted Rashba parameter values were found to be about 12–15 × 10–12 eV*m. These values are stronger than the previous reported Rashba parameters obtained from the 2-DEGs in other heterostructure systems and several layered 2D materials. The observed strong spin–orbit coupling (SOC) is attributed to the strong internal electric field generated by the lattice mismatch between the CaZrO3 layer and SrTiO3 substrate. This pioneering strong SOC of the 2-DEG at the CaZrO3/SrTiO3 heterointerface may play a pivotal role in the developing future metal oxide-based quantum nanoelectronics devices. [ABSTRACT FROM AUTHOR]

A fundamental understanding of film processing conditions and its effect on the microstructure, crystallinity, and electrical properties of thick layers of a GdBa2Cu3O7-δ (GdBaCuO) superconductor is necessary to optimize material requirements for its applications. In this work, the authors investigated the surface microstructure, crystalline quality, and superconducting properties of GdBaCuO thick films on (100) SrTiO3 single crystal substrates prepared by pulsed laser deposition (PLD). To clarify the effect of PLD growth conditions the substrate temperature, oxygen partial pressure, and laser fluence were systematically varied, then their impact was correlated on the microstructure and superconducting properties of thick layers of GdBaCuO films. By optimizing these growth conditions, the authors successfully obtained preferentially c-axis textured and superconducting films with a uniform and homogeneous layer up to 3.8 μm thick. Based on these results, the authors provide a key guiding principle in achieving thick highly c-axis textured superconducting GdBaCuO films using PLD. [ABSTRACT FROM AUTHOR]

We successfully grew AIrO3 ( \(A=\) Ca, Ba Sr) incorporated Bi2 Sr2 CaCu2O \(_{8+\delta}\) (BSCCO) films using pulsed laser deposition technique with post-growth ex situ treatment. The incorporation was accomplished by initially growing AIrO3 iridate nanoparticles on top of a single crystal MgO (100) substrate followed by a BSCCO layer. The composite film was then partial melted at 890 °C for 15 min and annealed at 850 °C for 5 h in ambient air. In this way, we controlled the type of iridate nanoparticles, which were embedded inside the superconducting BSCCO matrix. We observed that the superconducting transition temperature T \(_{{c-{\rm zero}}}\) , activation energy \(U_{o}\) , and magnetoresistance can be tuned depending on the type of iridate incorporation. [ABSTRACT FROM AUTHOR]

Iridate nanoparticle AIrO3 ( A = Sr, Ba) incorporated Bi2Sr2CaCu2O8 + δ (Bi-2212) thin films were successfully grown using pulsed laser deposition with post-growth ex situ heat treatment. Nanosized particles of SrIrO3 (Sr-iridate) and BaIrO3 (Ba-iridate) were deposited on top of MgO (100) substrate, followed by Bi-2212 layers to investigate their effects on the physical and superconducting properties of Bi-2212 thin films. The number of laser pulses was changed from 450 to 1800 to control the density of iridates in the Bi-2212 matrix. The composite film is then partial-melted at 890 °C for 15 min and annealed at 850°C for 5 h in ambient air. Scanning electron microscopy shows that the surfaces of thin films with iridates are more compact with minimal voids and porosity than those of pure Bi-2212 thin films. Both types of iridate incorporation suppress Tc-zero of Bi-2212 thin films. Incorporating Sr-iridate in the Bi-2212 strongly affects Tc-zero than those with Ba-iridate at low density. However, both iridate incorporations result in the expansion of the c-axis lattice constant and variation of Bi/Sr ratio of Bi-2212 films. On the other hand, we observed improvement of the activation energy, U0, as well as the self-field critical current density, Jc(0), of Bi-2212 films with incorporated iridates even with suppressed Tc-zero. [ABSTRACT FROM AUTHOR]

We grew fully strained epitaxial LaCrO3 (LCO) films on SrTiO3(001) under layer-by-layer control up to the film thickness of t = 130 nm using a pulsed laser deposition method. The spin axis of the antiferromagnetic LCO film was systematically examined as a function of t by using Cr L2,3-edge x-ray magnetic linear dichroism (XMLD). The XMLD results manifest a spin reorientation transition (SRT) across a transition thickness of tT ∼ 60 nm. This SRT is well explained in terms of two competing magnetic anisotropy energies of the surface/interface (KS) and the LCO film itself (KV). [ABSTRACT FROM AUTHOR]