InSe/Se范德瓦尔斯异质结的可控制备及其高响应度广光谱光电探测器（英文）

Controlled Fabrication In Se/Se Van Der Waals Heterojunction for High Responsivity Broadband Photodetectors

为了实现紫外-可见波段的高响应度/低成本的广光谱光电探测,我们制备了基于一维p型Se微米线与二维n型InSe纳米片的混维范德瓦尔斯异质结广光谱探测器。得益于Se微米线与二维层状结构InSe纳米片的高结晶质量,该器件在紫外-可见光广光谱范围都具有非常高的响应度,该器件的响应截止边为700 nm。值得指出的是,该器件在-5 V的偏压下,对460 nm的光源响应度可以达到108 mA/W,该数值比原来的Se探测器高了800%。这项研究有利于拓展我们对范德瓦尔斯异质结的认识,也为今后制备高性能的低维光电探测器提供了一种新的途径。

In order to reduce far-field divergence angle of semiconductor laser along slow axis and improve slow axis beam quality,a new type of adiabatic package structure is proposed.With this structure,the strength of thermal lens effect of the laser chip can be reduced.We have simulated the lateral heat distribution of broad-area semiconductor laser chip with the new structure by ANSYS 18.0,the model is based on the law of heat conduction(Fourier’s law).The beam quality of 808 nm In0.08Ga0.78Al0.14As/Al0.37GaAs broad-area semiconductor laser was experimentally investigated.Measurement is based on charge coupled device(CCD)image acquisition analysis method.The results show that the adiabatic package structure can reduce slow axis divergence angle by about 40%,and the slow axis divergence angle is more stable as the working currents change.Moreover,the corresponding beam parameter product(BPP)and beam quality factor M2 are also reduced by about 33%and 30%.The narrower the contact width between chip and heat sink is,the better the effect of the improvement will be.The introduction of the air gap in the adiabatic package leads to a deterioration of photoelectric characteristics.The output power P reduces by 14%,electro-optical conversion efficiencyηreduces by 8.7%.Adiabatic package method has guiding significance to the improvement of the slow axis beam quality of 808 nm broad-area semiconductor lasers.