Atomically thin mononitrides SiN and GeN: New two-dimensional wide band gap semiconductors Yan Qian, Zhengwei Du, Renzhu Zhu, Haiping Wu, Erjun Kan and Kaiming Deng EPL, 122 4 (2018) 47002 Published online: 27 June 2018 DOI: 10.1209/0295-5075/122/47002