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The utility of colloidal semiconductor quantum dots as a source of photons and charge carriers for photonic and photovoltaic applications has created a large field of research focused on tailoring and broadening their functionality beyond what an exciton can provide. One approach towards expanding the range of characteristics of photons and charge carriers from quantum dots is through doping impurity ions ( e.g. Mn 2+ , Cu + , and Yb 3+ ) in the host quantum dots. In addition to the progress in synthesis enabling fine control of the structure of the doped quantum dots, a mechanistic understanding of the underlying processes correlated with the structure has been crucial in revealing the full potential of the doped quantum dots as the source of photons and charge carriers. In this review, we discuss the recent progress made in gaining microscopic understanding of the photophysical pathways that give rise to unique dopant-related luminescence and the generation of energetic hot electrons via exciton-to-hot electron upconversion.
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This content will become publicly available on August 21, 2026
The role of effective mass on semiconductor charge carrier localization as revealed by the split operator method
Charge carriers in a solid-state material are modeled as free particles with a variable “effective” mass that is derived from the curvature of the conduction/valence band. These effective masses of electrons and holes are unique to each material and are dependent on the internal band structure (e.g., heavy vs light holes). Quantum mechanical characterizations of nanomaterials employ effective mass theory using particle-in-a-box paradigms to calculate quantum confinement (i.e., localization) energies. However, semiconductor heterostructures, such as core/shell quantum dots, have spatially variant masses, and as a result, the Schrodinger equation must be solved via a numerical approach incorporating the Hermitian kinetic energy operator T̂∼∇m−1x∇. To this end, the split operator “spectral” method was modified with the variable mass kinetic energy operator to study a variety of core/shell quantum dots. The results reveal a preferential localization of charge carriers into regions of high effective mass, which has a non-negligible effect on structure/property relationships that are increasingly being used to guide the synthesis of semiconductor heterostructures, such as “giant” type II quantum dots.
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- Award ID(s):
- 2345581
- PAR ID:
- 10647240
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 163
- Issue:
- 7
- ISSN:
- 0021-9606
- Subject(s) / Keyword(s):
- Quantum confinement Effective mass Quantum dots Semiconductors Split-operator method Spectral methods Nanomaterials Schrodinger equations
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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