Theoretical Studies on the Transport Properties of 2D InAs Colloidal QD Films
Panagiotis Rodosthenous a, Marco Califano a, Francisco M. Gómez-Campos b, Erik S. Skibinsky-Gitlin b, Salvador Rodríguez-Bolívar b
a University of Leeds, United Kingdom
b Universidad de Granada, Avenida de Fuente Nueva, s/n, Granada, Spain
Proceedings of International Conference on Emerging Light Emitting Materials (EMLEM23)
Peyia, Cyprus, 2023 November 13th - 15th
Organizers: Grigorios Itskos, Maksym Kovalenko and Maryna Bodnarchuk
Oral, Panagiotis Rodosthenous, presentation 034
Publication date: 18th August 2023

Two-dimensional quantum dot (QD) arrays are considered promising candidates for a wide range of applications that heavily rely on their transport properties [1] [2]. Existing QD films, however, were used to be made of either toxic or heavy-metal-based materials, limiting their applications and the commercialization of devices. As a result, there is an increasing trend in looking for non-toxic alternatives, in an effort to replace the toxic ones and enhance their commercial applications [3]. This theoretical study, provided a detailed analysis of the transport properties of environmentally-friendly colloidal QD films (In-based and Ga-based), identifying possible alternatives to their currently used toxic counterparts. Specifically, 2D colloidal QD films based on InAs QDs were modeled and compared with existing relevant experimental work, highlighting how changing the composition, stoichiometry, and the distance between the QDs in the array affects the resulting carrier mobility for different operating temperatures. Additionally, this work showed that by engineering the QD stoichiometry, it is possible to enhance the film’s transport properties, paving the way for the synthesis of higher-performance devices. The mobility of the films was calculated for temperatures ranging between 50 and 350 K (corresponding to a realistic range for device operation).

The isolated QDs were generated following the state-of-the-art semiempirical pseudopotential method, forming a periodic array when placed in a square lattice. Following a tight-binding model, the electronic structure of the system was calculated, i.e., the QD film miniband structure, from which the transport properties (e.g. carrier mobility) were extracted. The main scattering mechanism was considered due to the presence of impurity dots (smaller dots compared to the periodic dots), and thus a 1% density of impurities was assumed as a realistic value in accordance with experimental samples [4].

The results of this study provided a strong indication that 2D films based on InAs colloidal QDs can become a potential replacement for existing CdSe, and Pb-based films while having similar temperature decay trends with other experimental results on InAs QD films.

This work was undertaken on ARC3, part of the High Performance Computing Facilities at the University of Leeds, UK. P.R. gratefully acknowledges financial support from EPSRC through a Doctoral Training Grant. F.M.G.C., S.R.B., and E.S.S.-G. received financial support from Project No. P18-RT-3303 from the Spanish Junta de Andalucia. M.C. is thankful to the School of Electronic and Electrical Engineering, University of Leeds, for financial support.

We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info