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Abstract Information industry is one of the major drivers of the world economy. Its rapid growth, however, leads to severe heat problem which strongly hinders further development. This calls for a non-charge-based technology. Magnon, capable of transmitting spin information without electron movement, holds tremendous potential in post-Moore era. Given the cornerstone role of the field effect transistor in modern electronics, creating its magnonic equivalent is highly desired but remains a challenge. Here, we demonstrate a nonvolatile three-terminal lateral magnon field effect transistor operating at room temperature. The device consists of a ferrimagnetic insulator (Y3Fe5O12) deposited on a ferroelectric material [Pb(Mg1/3Nb2/3)0.7Ti0.3O3 or Pb(Zr0.52Ti0.48)O3], with three Pt stripes patterned on Y3Fe5O12 as the injector, gate, and detector, respectively. The magnon transport in Y3Fe5O12 can be regulated by the gate voltage pulses in a nonvolatile manner with a high on/off ratio. Our findings provide a solid foundation for designing energy-efficient magnon-based devices.

Recently, supershear Rayleigh waves (SRWs) have been proposed to characterize the biomechanical properties of soft tissues. The SRWs propagate along the surface of the medium, unlike surface Rayleigh waves, SRWs propagate faster than bulk shear waves. However, their behavior and application in biological tissues is still elusive. In brain tissue elastography, shear waves combined with magnetic resonance elastography or ultrasound elastography are generally used to quantify the shear modulus, but high spatial resolution elasticity assessment in 10 μm scale is still improving. Here, we develop an air-coupled ultrasonic transducer for noncontact excitation of SRWs and Rayleigh waves in brain tissue, use optical coherent elastography (OCE) to detect, and reconstruct the SRW propagation process; in combing with a derived theoretical model of SRWs on a free boundary surface, we quantify the shear modulus of brain tissue with high spatial resolution. We first complete validation experiments using a homogeneous isotropic agar phantom, and the experimental results clearly show the SRW is 1.9649 times faster than the bulk shear waves. Furthermore, the propagation velocity of SRWs in both the frontal and parietal lobe regions of the brain is all 1.87 times faster than the bulk shear wave velocity. Finally, we evaluated the anisotropy in different brain regions, and the medulla oblongata region had the highest anisotropy index. Our study shows that the OCE system using the SRW model is a new potential approach for high-resolution assessment of the biomechanical properties of brain tissue.

This work aims to depth-resolved quantitatively analyze the effect of different stromal ablation amounts on the corneal biomechanical properties during small incision lenticule extraction (SMILE) using optical coherence elastography (OCE). A 4.5-MHz ultrasonic transducer was used to excite elastic waves in the corneal tissue. The OCE system combined with the antisymmetric Lamb wave model was employed to achieve a high-resolution, high-sensitivity, and depth-resolved quantitative detection of the corneal Young’s modulus. Eighteen rabbits were randomly divided into three groups; each group had six rabbits. The first and second groups underwent -3D and -6D SMILE surgeries, and the third group was the control group, respectively. Young’s modulus of the corneal cap and residual stromal bed (RSB) were both increased after SMILE, which shared the stress under intraocular pressure (IOP). Furthermore, the Young’s modulus of both the corneal cap and RSB after 3D SMILE group were significantly lower than that in the -6D group, which indicated that the increases in the post-operative corneal Young’s modulus were positively correlated with the amount of stromal ablation. The OCE system for quantitative spatial characterization of corneal biomechanical properties can provide useful information on the extent of safe ablation for SMILE procedures.

We have proved that Cs2SnI6−xBrx (x = 0–6) can be eutectic in the whole composition, and the eutectic phase has the similar cubic symmetry with both of the end phases (space group of Fm3¯m). The lattice constant decreases from around 11.67 Å (x = 0) to around 10.83 Å (x = 6). Hall-plot analysis shows that the strain varies sharply near the two end materials, while the strain is almost independent of Br content at the middle Br content. The bandgap, on the other hand, increases from 1.26 eV to 2.93 eV with increasing the Br content, which might be expected in fabricating the continuous junction solar cells.

Bi2FeVO7 was prepared by a solid-state reaction technique for the first time and the structural and photocatalytic properties of Bi2FeVO7 were studied. The results shows that this compound crystallized in the tetragonal crystal system with space group I4/mmm. Moreover, the band gap of Bi2FeVO7 was estimated to be about 2.22(6) eV. For the photocatalytic water splitting reaction, H2 or O2 evolution was observed from pure water with Bi2FeVO7 as the photocatalyst by ultraviolet light irradiation. Degradation of aqueous methylene blue (MB) dye by photocatalytic way over this compound was further studied under visible light irradiation. Bi2FeVO7 shows higher catalytic activity compared to TiO2 (P-25) for MB photocatalytic degradation under visible light irradiation. Complete removal of aqueous MB was realized after visible light irradiation for 170 min with Bi2FeVO7 as the photocatalyst. The reduction of the total organic carbon (TOC) and the formation of inorganic products, SO2-4 and NO-3 revealed the continuous mineralization of aqueous MB during the photocatalytic course. [ABSTRACT FROM AUTHOR]

Bi2FeVO7 was prepared by a solid-state reaction technique for the first time and the structural and photocatalytic properties of Bi2FeVO7 were studied. The results shows that this compound crystallized in the tetragonal crystal system with space group I4/mmm. Moreover, the band gap of Bi2FeVO7 was estimated to be about 2.22(6) eV. For the photocatalytic water splitting reaction, H2 or O2 evolution was observed from pure water with Bi2FeVO7 as the photocatalyst by ultraviolet light irradiation. Degradation of aqueous methylene blue (MB) dye by photocatalytic way over this compound was further studied under visible light irradiation. Bi2FeVO7 shows higher catalytic activity compared to TiO2 (P-25) for MB photocatalytic degradation under visible light irradiation. Complete removal of aqueous MB was realized after visible light irradiation for 170 min with Bi2FeVO7 as the photocatalyst. The reduction of the total organic carbon (TOC) and the formation of inorganic products, SO2-4 and NO-3 revealed the continuous mineralization of aqueous MB during the photocatalytic course. [ABSTRACT FROM AUTHOR]