Insightful knowledge on quantum nanostructured materials is paramount to engineer and exploit their vast gamut of applications.Here,a formalism based on the single-band effective mass equation was developed to determi...Insightful knowledge on quantum nanostructured materials is paramount to engineer and exploit their vast gamut of applications.Here,a formalism based on the single-band effective mass equation was developed to determine the light absorption of colloidal quantum dots(CQDs)embedded in a wider bandgap semiconductor host,employing only three parameters(dots/host potential barrier,effective mass,and QD size).It was ascertained how to tune such parameters to design the energy level structure and consequent optical response.Our findings show that the CQD size has the biggest effect on the number and energy of the confined levels,while the potential barrier causes a linear shift of their values.While smaller QDs allow wider energetic separation between levels(as desired for most quantumbased technologies),the larger dots with higher number of levels are those that exhibit the strongest absorption.Nevertheless,it was unprecedently shown that such quantum-enabled absorption coefficients can reach the levels(10^(4)–10^(5) cm^(−1))of bulk semiconductors.展开更多
基金This work was funded by FCT(Fundação para a Ciência e Tecnologia,I.P.)under the projects UIDB/50025/2020SuperSolar(PTDC/NAN-OPT/28430/2017)+2 种基金TACIT(PTCD/NAN-OPT/28837/2017)M.Alexandre also acknowledges funding by FCT,I.P.through the grant SFRH/BD/148078/2019We also acknowledge the support of SYNERGY,H2020-WIDESPREAD-2020-5,CSA,proposal n°952169.
文摘Insightful knowledge on quantum nanostructured materials is paramount to engineer and exploit their vast gamut of applications.Here,a formalism based on the single-band effective mass equation was developed to determine the light absorption of colloidal quantum dots(CQDs)embedded in a wider bandgap semiconductor host,employing only three parameters(dots/host potential barrier,effective mass,and QD size).It was ascertained how to tune such parameters to design the energy level structure and consequent optical response.Our findings show that the CQD size has the biggest effect on the number and energy of the confined levels,while the potential barrier causes a linear shift of their values.While smaller QDs allow wider energetic separation between levels(as desired for most quantumbased technologies),the larger dots with higher number of levels are those that exhibit the strongest absorption.Nevertheless,it was unprecedently shown that such quantum-enabled absorption coefficients can reach the levels(10^(4)–10^(5) cm^(−1))of bulk semiconductors.
