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The lack of a bulk second-order nonlinearity (χ⁽²⁾) in silicon nitride (Si₃N₄) keeps this low-loss, CMOS-compatible platform from key active functions such as Pockels electro-optic (EO) modulation and efficient second harmonic generation (SHG). We demonstrate a successful induction ofχ⁽²⁾in Si₃N₄through electrical poling with an externally-applied field to align the Si-N bonds. This alignment breaks the centrosymmetry of Si₃N₄, and enables the bulkχ⁽²⁾. The sample is heated to over 500°C to facilitate the poling. The comparison between the EO responses of poled and non-poled Si₃N₄, measured using a Si₃N₄micro-ring modulator, shows at least a 25X enhancement in ther₃₃EO component. The maximumχ⁽²⁾we obtain through poling is 0.30pm/V. We observe a remarkable improvement in the speed of the measured EO responses from 3 GHz to 15 GHz (3 dB bandwidth) after the poling, which confirms theχ⁽²⁾nature of the EO response induced by poling. This work paves the way for high-speed active functions on the Si₃N₄platform.

All‐sky imagers located in Asiago, Italy (45.87^oN, 11.53^oE; 40.7^omagnetic latitude) and Sutherland, South Africa (32.37^oS, 20.81^oE; −40.7^omagnetic latitude) are used to study magnetically conjugate medium scale traveling ionospheric disturbances (MSTIDs). We present initial results from the first year of joint Asiago‐Sutherland data sets from July 2016 to June 2017. The 630.0‐nm airglow perturbations showing different kinds of waves were frequently observed. Some of these wave events resemble MSTIDs propagating south‐westward in Asiago, typical direction observed at other longitude sectors in the northern hemisphere. They are mostly observed as single bands propagating through the field of view of the all‐sky imagers. We select and analyze five cases of magnetically conjugate bands associated with MSTIDs. The bands observed at Sutherland move mainly westward, noticeably different from the north‐west direction of propagation of MSTIDs observed in the southern hemisphere. We compare the MSTIDs propagation speeds and find that three cases show larger values at Sutherland. When we compare the zonal speeds all the cases show larger values at Sutherland. On average, the propagation speed at Sutherland is 20% larger and the zonal speed is ~35% larger. The westward motion at Sutherland is explained by taking onto account how its magnetic declination (~24^oW) affects the orientation of the bands. The larger speed at Sutherland is due to the weaker Earth's magnetic field in the southern hemisphere and the particular configuration of the magnetic field lines in this longitude sector.