The modified Becke–Johnson exchange potential approximation is applied to predict the band structure,optical parameters and electron density of SnMg_(2)O_(4)and SnZn_(2)O_(4).The local density approximation,generaliz...The modified Becke–Johnson exchange potential approximation is applied to predict the band structure,optical parameters and electron density of SnMg_(2)O_(4)and SnZn_(2)O_(4).The local density approximation,generalized gradient approximation(GGA),EV-GGA significantly underestimate the direct band gap values compared to modified Becke–Johnson approximation.The band gap dependent optical parameters such as dielectric constant,index of refraction,reflectivity,and optical conductivity are calculated and analyzed.A prominent feature of cation replacement is observed and analyzed for these studied compounds.The replacement of the cation Mg by Zn leads to a significant reduction in the value of band gap and consequently affects its dependant optical parameters.This variation is of crucial importance for device fabrication in different regions of the spectrum.展开更多
Oxide spinels have potential applications in optoelectronics and optics fields.In this work the electronic band structure and optical properties of GeMg2O4 and GeCd2O4 are calculated by first principles technique base...Oxide spinels have potential applications in optoelectronics and optics fields.In this work the electronic band structure and optical properties of GeMg2O4 and GeCd2O4 are calculated by first principles technique based on the new potential approximation known as the modified Becke-Johnson exchange potential approximation(mBJ).The local density and generalized gradient approximations significantly underestimate the direct band gap values compared to the mBJ.The band gap dependent optical parameters such as dielectric constant,refractive index,reflectivity and optical conductivity are calculated and analyzed.The replacement of the cation is observed and analyzed for the compounds studied and a prominent change is noticed.The replacement of the cation Mg by Cd reduces the band gap and its dependent optical parameters.For device fabrication in different regions of the spectrum this variation is strongly recommended.展开更多
We employ the first-principles technique based on the modified Becke–Johnson(BJ)exchange potential for the prediction of the electronic band structure,optical properties,and electron density of the cubic MgIn_(2)O_(4...We employ the first-principles technique based on the modified Becke–Johnson(BJ)exchange potential for the prediction of the electronic band structure,optical properties,and electron density of the cubic MgIn_(2)O_(4)spinel compound.It is found that the calculated band gap value with the modified BJ approximation is significantly improved over the results based on the generalized gradient approximation and the local density approximation in comparison to the experimental data.The band gap dependent optical parameters such as the dielectric constant,refractive index,reflectivity,optical conductivity,and electron density are predicted.The optical response suggests that MgIn_(2)O_(4)is an applicant material in optoelectronic devices in various parts of the energy spectrum like MgAl_(2)O_(4)and MgGa_(2)O_(4).展开更多
基金the Deanship of Scientific Research at King Saud University under Grant No RPG-VPP-088.
文摘The modified Becke–Johnson exchange potential approximation is applied to predict the band structure,optical parameters and electron density of SnMg_(2)O_(4)and SnZn_(2)O_(4).The local density approximation,generalized gradient approximation(GGA),EV-GGA significantly underestimate the direct band gap values compared to modified Becke–Johnson approximation.The band gap dependent optical parameters such as dielectric constant,index of refraction,reflectivity,and optical conductivity are calculated and analyzed.A prominent feature of cation replacement is observed and analyzed for these studied compounds.The replacement of the cation Mg by Zn leads to a significant reduction in the value of band gap and consequently affects its dependant optical parameters.This variation is of crucial importance for device fabrication in different regions of the spectrum.
文摘Oxide spinels have potential applications in optoelectronics and optics fields.In this work the electronic band structure and optical properties of GeMg2O4 and GeCd2O4 are calculated by first principles technique based on the new potential approximation known as the modified Becke-Johnson exchange potential approximation(mBJ).The local density and generalized gradient approximations significantly underestimate the direct band gap values compared to the mBJ.The band gap dependent optical parameters such as dielectric constant,refractive index,reflectivity and optical conductivity are calculated and analyzed.The replacement of the cation is observed and analyzed for the compounds studied and a prominent change is noticed.The replacement of the cation Mg by Cd reduces the band gap and its dependent optical parameters.For device fabrication in different regions of the spectrum this variation is strongly recommended.
基金Supported by the Deanship of Scientific Research at King Saud University under Grant No RPG-VPP-088.
文摘We employ the first-principles technique based on the modified Becke–Johnson(BJ)exchange potential for the prediction of the electronic band structure,optical properties,and electron density of the cubic MgIn_(2)O_(4)spinel compound.It is found that the calculated band gap value with the modified BJ approximation is significantly improved over the results based on the generalized gradient approximation and the local density approximation in comparison to the experimental data.The band gap dependent optical parameters such as the dielectric constant,refractive index,reflectivity,optical conductivity,and electron density are predicted.The optical response suggests that MgIn_(2)O_(4)is an applicant material in optoelectronic devices in various parts of the energy spectrum like MgAl_(2)O_(4)and MgGa_(2)O_(4).
