Electronic structure, Dirac points and Fermi arc surface states in three-dimensional Dirac semimetal Na<sub>3</sub>Bi from angle-resolved photoemission spectroscopy

Electronic structure, Dirac points and Fermi arc surface states in three-dimensional Dirac semimetal Na₃Bi from angle-resolved photoemission spectroscopy

Liang Aiji¹, Chen Chaoyu¹, Wang Zhijun¹, Shi Youguo¹, Feng Ya¹, Yi Hemian¹, Xie Zhuojin¹, He Shaolong^{1, †,}, He Junfeng¹, Peng Yingying¹, Liu Yan¹, Liu Defa¹, Hu Cheng¹, Zhao Lin¹, Liu Guodong¹, Dong Xiaoli¹, Zhang Jun¹, Nakatake M², Iwasawa H², Shimada K², Arita M², Namatame H², Taniguchi M², Xu Zuyan³, Chen Chuangtian³, Weng Hongming^{1, 4}, Dai Xi^{1, 4}, Fang Zhong^{1, 4}, Zhou Xing-Jiang^{1, 4, ‡,}

Identification of the coexistence of the surface states with the three-dimensional bulk Dirac bands on the (100) surface of Na₃Bi. (a) Band structure along direction taken by 6.994 eV VUV-laser ARPES. (a1) is the original data while (a2) is the second derivative image of (a1) with respect to energy. (b) Band structure along direction over a large energy range taken by 6.994 eV VUV-laser ARPES. (b1) is the original data while (b2) is the second derivative image of (b1) with respect to energy. The bulk bands are marked by α and β in (b2). The gray dashed line is a guide to eyes for the SS band. (c)–(f) Band structures along direction on the (100) surface taken by ARPES with different photon energies. (g) The theoretically calculated band structure along direction on the (100) surface with surface states labeled as SS.