Triboelectric nanogenerators (TENGs) use the displacement current as a driving force to convert mechanical energy into electric power, which has made great contributions to micro‐nano energy harvesting, self‐powered systems, and the sustainable development of mankind. To date, it is accepted that the output of TENGs is only dependent on the polarization effect. This study reveals that this view is incomplete and, in reality, the magnetization effect also makes a significant contribution to the output of TENGs. For the first time, a novel insight on the output of TENGs is discovered through the theoretical derivation and analysis of Maxwell's equations in ferromagnetic medium. Experimentally, TENGs based on ferromagnetic media are constructed, which exhibit higher output than that of non‐ferromagnetic media based. Interestingly, the output behavior of ferromagnetic media based TENGs is strongly related to the external magnetic field ambient, which is well demonstrated. The discovered output characteristics of TENGs are precisely derived from the working principle of TENGs, simultaneously, a completed and unified theoretical system is constructed for TENGs. This significant discovery and theory will be an indispensable supplement to the existing research on TENGs and also provide a general guidance and deeper understanding of the TENG.

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The thermal effect of diode pumped solid-state laser (DPSSL) has always been a main problem limiting the further improvement of laser performance. In this paper, based on the special heat load distribution of the laser crystal of diode partially end-pumped slab (Innoslab) laser, a multi-stage manifold rectangular microchannel heat sink (MCHS) with high thermal conductivity path (HTCP) is designed. The multi-stage manifold provides the MCHS more fluid-solid heat transfer area near the heat gathering area, while the HTCP provides a path for heat transmission from pump end to the body of MCHS. According to simulation calculation, the highest temperature of laser crystal has been reduced by nearly 50? due to the addition of HTCP. Then the MCHS is fabricated by MEMS technology and the laser crystal is replaced by simulated heat source. Compared with the MCHS without the HTCP, the thermal resistance of the MCHS with HTCP is reduced by 6.4%, which proves the effectiveness of HTCP in heat dissipation of Innoslab laser crystal.

With the power level of diode-pumped solid-state laser (DPSSL) rising continuously, its thermal effect has become the main problem limiting the laser performance. In this paper, based on the heat distribution of diode partially end-pumped slab (Innoslab) laser, a shunt rectangular microchannel heat sink with locally enhanced heat dissipation is designed. Firstly, multi-stage parallel short channels are designed in the heat concentration area to enhance the solid-liquid heat exchange in this area, and the effects of structure and working conditions on its heat dissipation performance are investigated. Secondly, the copper layer is introduced into the end face of the low thermal conductivity crystal to form a high thermal conductivity path, which alleviates the heat accumulation inside the crystal. Under a certain condition, compared with the traditional liquid-cooled plate system, the maximum temperature of the laser crystal is reduced from 169.62 to 118.18 °C, the pressure drop is reduced by 66.75%, and the total mass of the system is reduced to 4.87% of the original system, which effectively improves the practical performance of the device.