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We present a study on the development of Finnish first-year physics majors' attitudes towards physics, as measured by the Colorado Learning Attitudes about Science Survey, before, during, and after the period of mandatory remote learning due to the coronavirus pandemic. We find that in the years before the pandemic, these attitudes did not change, but the period of extended remote learning due to the pandemic had a negative effect on the students' expertlike views. Similarly, the students who experienced the remote learning period in high school displayed a lower level of expertlike thinking as they entered university. As contact teaching resumed, moderate positive gains were seen, bridging some but not all of the gap in student attitudes left by the pandemic.

Harnessing the full power of memristors as artificial synapses demands a simple and scalable crossbar architecture enabling their seamless integration into diverse applications. This Letter presents the 3 × 3 memristor crossbar array configuration featuring a grid of interconnected devices. The composition includes Al as the reactive top electrode connecting the device columns and Gd1−xCaxMnO3 (GCMO, x = 0.8) serving as the bottom electrode connecting the device rows as well as the memristive material eliminating the need for additional layers and fabrication steps. Controlled-sized vias through insulating the Al2O3 layer connect the electrodes forming the active interface. The idea is validated with a test sample of 3 × 3 crossbars with the Au/GCMO/Al structure, Au enabling Ohmic contact to GCMO, with device resistive switching ratios mostly around 102 and yield of over 90%. The devised crossbar structure could provide a highly scalable, yet simple, geometry suitable for synaptic networks. [ABSTRACT FROM AUTHOR]

A crucial role in the miniaturization of electronic and photonic components is played by the integration of ferroelectric thin films on silicon (Si) or silicon nitride (SiN) based platforms. Since the properties of ferroelectric thin films strongly depend on their texture quality and crystallographic orientation, the integration of thin films on these platforms is far from trivial. Consequently, this leads to slow, complex and expensive integration processes. To bridge this gap, a high-throughput method for the integration of highly textured ferroelectric thin films on Si or SiN-based platforms is needed. Therefore, we have investigated a method to facilitate the integration of fiber textured ferroelectric thin films by using an ultrathin (∼7 nm) self out-of-plane oriented La2O2CO3 template film. In this paper, we report a local deposition route of the La2O2CO3 thin film by the scalable inkjet printing method, its inherent out-of-plane crystal orientation, and its lattice match with various ferroelectric thin films. The use of the La2O2CO3 template film as an integration tool for (Pb(Zr,Ti)O3, BaTiO3, and BiFeO3) thin films eventually results in strongly fiber-textured ferroelectric stacks, regardless of substrate type. Consequently, the La2O2CO3 thin film has the potential to serve as a high-throughput integration tool for fiber textured ferroelectric thin films on Si or SiN-based platforms. Moreover, this integration tool could pave the way for large-scale miniaturization of photonic or electronic devices such as phase modulators, resonators, capacitors, etc. [ABSTRACT FROM AUTHOR]

Despite great attention toward transition metal tellurates especially M3TeO6 (M = transition metal) in magnetoelectric applications, control on single phasic morphology-oriented growth of these tellurates at the nanoscale is still missing. Herein, a hydrothermal synthesis is performed to synthesize single-phased nanocrystals of two metal tellurates, i.e., Ni3TeO6 (NTO with average particle size ∼37 nm) and Cu3TeO6 (CTO ∼ 140 nm), using NaOH as an additive. This method favors the synthesis of pure NTO and CTO nanoparticles without the incorporation of Na at pH = 7 in MTO crystal structures such as Na2M2TeO6, as it happens in conventional synthesis approaches such as solid-state reaction and/or coprecipitation. Systematic characterization techniques utilizing in-house and synchrotron-based characterization methods for the morphological, structural, electronic, magnetic, and photoconductivity properties of nanomaterials showed the absence of Na in individual particulate single-phase MTO nanocrystals. Prepared MTO nanocrystals also exhibit slightly higher antiferromagnetic interactions (e.g., TN-NTO = 57 K and TN-CTO = 68 K) compared to previously reported MTO single crystals. Interestingly, NTO and CTO show not only a semiconducting nature but also photoconductivity. The proposed design scheme opens the door to any metal tellurates for controllable synthesis toward different applications. Moreover, the photoconductivity results of MTO nanomaterials prepared serve as a preliminary proof of concept for potential application as photodetectors. [ABSTRACT FROM AUTHOR]

A complex deposition process of high-temperature superconducting (HTS) thin films and coated conductors is usually optimized by concentrating on the crystalline quality of the material, thus getting the best possible critical temperature and self-field properties. However, most of the HTS power applications that are based on coated conductors act at high magnetic fields, and thus an alternative approach focusing on the formation of an optimal network of columnar flux pinning centers is more reasonable. Therefore, we systematically show how a lengthening of the deposition distance produces perfectly aligned and distinctly longer self-assembled BaZrO3 (BZO) nanorods within the YBa2Cu3O6+x (YBCO) matrix. This method unambiguously enhances in-field properties such as pinning force, critical current density, and its isotropy along the YBCO c axis. The experimental results, especially formation of the c peak where the relative length of the nanorod is a key issue, are confirmed by the vortex dynamics simulations. Finally, we present a semiquantitative model governing the formation of nanorods that explains the experimentally observed improved nanorod growth as a function of the deposition distance via the associated variation of the fractional partial pressure between atomic species within the laser plume. [ABSTRACT FROM AUTHOR]