The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two ...The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two non-centrosymmetric halidepnictides,[Cd_(2)P]_(2)[CdBr_(4)](CPB)and[Cd_(2)As]_(2)[CdBr_(4)](CAB) were reported.The complete octet binding electrons of pnictogens were constructed by four Cd-P pola covalent bonds under the anchoring effect of halogens,creating an extremely flat valence band maximum with band dispersion of only 0.17 eV.As expected,the balance of the covalency and ionicity in CPB and CAB was successfully realized,leading to a wide band gap of 2.58 eV and 1.88 eV.Remarkably,CPB no only has a widest band gap among Cd-containing pnictides,but also exhibits a SHG effect of 1.2×AgGaS_(2).moderate birefringence(0.088@visible light and calcd.0.043@2050 nm)and a wide IR transmission range.This is the first time that the octet binding electrons construction strategy was utilized to design non diamond like NLO pnictides with excellent performances.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22305174,22375147,52332001,51890862,51902308 and 21921001)the Natural Science Foundation of Fujian Province(No.2021J05097)the Natural Science Foundation of Tianjin City(No.22JCYBJC01380)。
文摘The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two non-centrosymmetric halidepnictides,[Cd_(2)P]_(2)[CdBr_(4)](CPB)and[Cd_(2)As]_(2)[CdBr_(4)](CAB) were reported.The complete octet binding electrons of pnictogens were constructed by four Cd-P pola covalent bonds under the anchoring effect of halogens,creating an extremely flat valence band maximum with band dispersion of only 0.17 eV.As expected,the balance of the covalency and ionicity in CPB and CAB was successfully realized,leading to a wide band gap of 2.58 eV and 1.88 eV.Remarkably,CPB no only has a widest band gap among Cd-containing pnictides,but also exhibits a SHG effect of 1.2×AgGaS_(2).moderate birefringence(0.088@visible light and calcd.0.043@2050 nm)and a wide IR transmission range.This is the first time that the octet binding electrons construction strategy was utilized to design non diamond like NLO pnictides with excellent performances.
