论文标题
像石墨烯一样c $ _3 $ n中的激子效应
Excitonic effects in graphene-like C$_3$N
论文作者
论文摘要
单层C $ _3 $ N是一种新兴的二维间接带隙半导体，具有有趣的机械，热和电子性能。在这项工作中，我们介绍了c $ _3 $ n电子和介电性能的描述，重点是所谓的动量分辨激动型激子结构。计算激发能和振荡器强度以表征明亮和黑暗状态，并就晶体对称性进行了讨论。对于有限传输的动量，观察到激活激活的激活：的确，我们在$ \ sim $ 0.9 eV处发现了一个主动间接激子，显着低于1.96 eV的直接光学间隙，在最低状态下，具有激子结合能在0.6-0.9 eV范围内。至于其他2D材料，我们发现了接近$γ$的准线性激发式分散剂，但是它显示了与c $ _3 $ n的间接频带间隙以及相关消除剂的黑暗性质相关的向下凸度。
Monolayer C$_3$N is an emerging two-dimensional indirect band gap semiconductor with interesting mechanical, thermal, and electronic properties. In this work we present a description of C$_3$N electronic and dielectric properties, focusing on the so-called momentum-resolved exciton band structure. Excitation energies and oscillator strengths are computed in order to characterize bright and dark states, and discussed also with respect to the crystal symmetry. Activation of excitonic states is observed for finite transferred momenta: Indeed, we find an active indirect exciton at $\sim$ 0.9 eV, significantly lower than the direct optical gap of 1.96 eV, with excitonic binding energies in the range 0.6-0.9 eV for the lowest states. As for other 2D materials, we find a quasi-linear excitonic dispersion close to $Γ$, which however shows a downward convexity related to the indirect band gap of C$_3$N as well as to the dark nature of the involved excitons.
