Cipriano Luis A, Di Liberto Giovanni, Tosoni Sergio, Pacchioni Gianfranco
Dipartimento di Scienza dei Materiali, Università di Milano - Bicocca, via R. Cozzi 55, 20125 Milano, Italy.
Nanoscale. 2020 Sep 7;12(33):17494-17501. doi: 10.1039/d0nr03577g. Epub 2020 Aug 18.
In this work we investigate the role of quantum confinement in group III-V semiconductor thin films (2D nanostructures). To this end we have studied the electronic structure of nine materials (AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs and InSb) by means of Density Functional Theory (DFT) calculations using a screened hybrid functional (HSE06). We focus on the structural and electronic properties of bulk and the (110) surfaces, for which we evaluate and rationalize the impact of system size to the band gap and band edge positions. Our results indicate that when the quantum confinement is strong, it mainly affects the position of the Conduction Band Minimum (CBM) of the semiconductor, while the Valence Band Maximum (VBM) is almost insensitive to the system size. The results can be rationalized in terms of electron and hole effective masses. Our conclusions, based on slabs, can be generalized to other cases of quantum confinement such as quantum dots, overcoming the need for an explicit consideration and calculation of the properties of semiconductor nanoparticles.
在这项工作中，我们研究了量子限制在III-V族半导体薄膜（二维纳米结构）中的作用。为此，我们通过使用屏蔽杂化泛函（HSE06）的密度泛函理论（DFT）计算，研究了九种材料（AlP、AlAs、AlSb、GaP、GaAs、GaSb、InP、InAs和InSb）的电子结构。我们关注体材料和（110）表面的结构和电子性质，为此我们评估并合理解释了系统尺寸对带隙和带边位置的影响。我们的结果表明，当量子限制很强时，它主要影响半导体导带最小值（CBM）的位置，而价带最大值（VBM）对系统尺寸几乎不敏感。这些结果可以根据电子和空穴的有效质量来合理解释。我们基于平板的结论可以推广到其他量子限制情况，如量子点，从而无需明确考虑和计算半导体纳米颗粒的性质。
