We have measured the rf magnetoconductivity of unidirectional lateral superlattices (ULSLs) by detecting the attenuation of microwave through a coplanar waveguide placed on the surface. ULSL samples with the principal axis of the modulation perpendicular (S ⊥ ) and parallel (S ) to the microwave electric field are examined. For low microwave power, we observe expected anisotropic behavior of the commensurability oscillations (CO), with CO in samples S ⊥ and S dominated by the diffusion and the collisional contributions, respectively. Amplitude modulation of the Shubnikov-de Haas oscillations is observed to be more prominent in sample S . The difference between the two samples is washed out with the increase of the microwave power, letting the diffusion contribution govern the CO in both samples. The failure of the intended directional selectivity in the conductivity measured with high microwave power is interpreted in terms of large-angle electron-phonon scattering.

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We have investigated microwave conductivity of unidirectonal lateral superlattices (ULSLs). In the vicinity of the ν = 2 quantum Hall state, striking microwave resonance is observed on the sample having the modulation along the rf electric field, while no resonance is discerned on the samples without modulation or with the modulation perpendicular to the rf electric field.

This paper proposes a new process to manufacture cover glass which overcomes a strength trade‐off between the face and the edge. In the process, alkali‐barrier films are deposited on glass faces before an ion‐exchange process in order to control face stress properties without inhibiting the edge strengthening. As a demonstration of the process, alkali‐alumino‐silicate glass sheets with SiO2 films were chemically strengthened, and their stress properties and strengths were investigated. As a result, thicker SiO2 films cause lower face DOL (Depth Of strengthened Layer), and it is observed that the faces have lower DOL than the edges. In strength tests corresponding to major fracture modes of smartphone cover glass, specimens with 80‐100 nm films have more balanced face performance and better edge impact strengths than the no‐film specimen.

This paper proposes a new process to manufacture cover glass which overcomes a strength trade-off between the face and the edge. In the process, alkali-barrier films are deposited on glass faces before an ion-exchange process in order to control face stress properties without inhibiting the edge strengthening. As a demonstration of the process, alkali-alumino-silicate glass sheets with SiO 2 films were chemically strengthened, and their stress properties and strengths were investigated. As a result, thicker SiO 2 films cause lower face DOL (Depth Of strengthened Layer), and it is observed that the faces have lower DOL than the edges. In strength tests corresponding to major fracture modes of smartphone cover glass, specimens with 80-100 nm films have more balanced face performance and better edge impact strengths than the no-film specimen.