Using first-principle calculations,we investigate the mechanical,structural,and electronic properties and formation energy of 25 kinds ofⅢ-Ⅴ binary monolayers in detail.A relative radius of the binary compound accor...Using first-principle calculations,we investigate the mechanical,structural,and electronic properties and formation energy of 25 kinds ofⅢ-Ⅴ binary monolayers in detail.A relative radius of the binary compound according to the atomic number in the periodic table is defined,and based on the definition,the 25 kinds ofⅢ-Ⅴ binary compounds are exactly located at a symmetric position in a symmetric matrix.The mechanical properties and band gaps are found to be very dependent on relative radius,while the effective mass of holes and electrons are found to be less dependent.A linear function between Young’s modulus and formation energy is fitted with a linear relation in this paper.The change regularity of physical properties of B-Ⅴ(Ⅴ=P,As,Sb,Bi)andⅢ-N(Ⅲ=Al,Ga,In,Tl)are found to be very different from those of otherⅢ-Ⅴ binary compounds.展开更多
The development of new materials,having exceptional properties in comparison to existing materials is highly required for bringing advancement in electronic and optoelectronic technologies.Keeping this fact,we investi...The development of new materials,having exceptional properties in comparison to existing materials is highly required for bringing advancement in electronic and optoelectronic technologies.Keeping this fact,we investigated structural,electronic,and optical properties of zincblende GaN doped with selected Zn concentrations(6.25%,12.50%,and 18.70%),using the first-principle calculations based on density functional theory with GGA+U.We conducted the entire study using the WIEN2K code.In this study,we calculated various significant parametric quantities such as cohesive energies,formation energies,bulk moduli,and lattice constants along with the study of optical and electronic properties by substituting Ga atoms with Zn atoms in 1×2×2 supercell.The structural stability is confirmed by studying the phonon dispersion curves which suggest that Zn:GaN material is stable against the 6.25%and 18.70%Zn concentrations while for 12.50%,it shows instability.The Hubbard values U=0,2,4,6 eV were added to GGA and the electronic properties were improved with the U=6 eV.Optical absorption was blue shifted while the refractive index and dielectric constant were increased with increasing the Zn concentrations.Electronic properties are enhanced due to the prime contribution of cations(Zn)3ri states.The optical and electronic properties are further discussed in detail in the entire study.展开更多
The progress of the design, synthesis, fluorescence properties and application of a new family of fluorescent molecular switches towards information processing at the molecular level was reviewed. On the basis of the ...The progress of the design, synthesis, fluorescence properties and application of a new family of fluorescent molecular switches towards information processing at the molecular level was reviewed. On the basis of the high fluorescence quantum yields and surroundings-sensitive fluorescent properties of the 5-methoxy-2-(2-pyridyl)-thiazole (2-MPT, 1) and a series of its derivatives as prepared, multiple binary logic and arithmetic functionalities were realized through encoding the controllable fluorescence switching properties with binary digit. Combined with the microfluidic platform, the fabrication of the molecular logic devices was attempted.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61564002 and 11664005)the Guizhou Normal University Innovation and Entrepreneurship Education Research Center Foundation(Grant No.0418010)the Joint Foundation of Guizhou Normal University(Grant No.7341)
文摘Using first-principle calculations,we investigate the mechanical,structural,and electronic properties and formation energy of 25 kinds ofⅢ-Ⅴ binary monolayers in detail.A relative radius of the binary compound according to the atomic number in the periodic table is defined,and based on the definition,the 25 kinds ofⅢ-Ⅴ binary compounds are exactly located at a symmetric position in a symmetric matrix.The mechanical properties and band gaps are found to be very dependent on relative radius,while the effective mass of holes and electrons are found to be less dependent.A linear function between Young’s modulus and formation energy is fitted with a linear relation in this paper.The change regularity of physical properties of B-Ⅴ(Ⅴ=P,As,Sb,Bi)andⅢ-N(Ⅲ=Al,Ga,In,Tl)are found to be very different from those of otherⅢ-Ⅴ binary compounds.
文摘The development of new materials,having exceptional properties in comparison to existing materials is highly required for bringing advancement in electronic and optoelectronic technologies.Keeping this fact,we investigated structural,electronic,and optical properties of zincblende GaN doped with selected Zn concentrations(6.25%,12.50%,and 18.70%),using the first-principle calculations based on density functional theory with GGA+U.We conducted the entire study using the WIEN2K code.In this study,we calculated various significant parametric quantities such as cohesive energies,formation energies,bulk moduli,and lattice constants along with the study of optical and electronic properties by substituting Ga atoms with Zn atoms in 1×2×2 supercell.The structural stability is confirmed by studying the phonon dispersion curves which suggest that Zn:GaN material is stable against the 6.25%and 18.70%Zn concentrations while for 12.50%,it shows instability.The Hubbard values U=0,2,4,6 eV were added to GGA and the electronic properties were improved with the U=6 eV.Optical absorption was blue shifted while the refractive index and dielectric constant were increased with increasing the Zn concentrations.Electronic properties are enhanced due to the prime contribution of cations(Zn)3ri states.The optical and electronic properties are further discussed in detail in the entire study.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20821091, 20705003 & 20733001)Peking University Financial Support
文摘The progress of the design, synthesis, fluorescence properties and application of a new family of fluorescent molecular switches towards information processing at the molecular level was reviewed. On the basis of the high fluorescence quantum yields and surroundings-sensitive fluorescent properties of the 5-methoxy-2-(2-pyridyl)-thiazole (2-MPT, 1) and a series of its derivatives as prepared, multiple binary logic and arithmetic functionalities were realized through encoding the controllable fluorescence switching properties with binary digit. Combined with the microfluidic platform, the fabrication of the molecular logic devices was attempted.
