Thin-Film, Low-Dimensional Materials and Their Heterojunctions for Optoelectronic Applications

Dear Colleagues,

You are cordially invited to contribute to this Special Issue of Materials, entitled “Thin-Film, Low-Dimensional Materials and Their Heterojunctions for Optoelectronic Applications”.

The technology for obtaining new optoelectronic materials, especially in film form, is a rapidly developing field of integrated photonics. Fabrication strategy plays a primary role here. In addition to traditional semiconductor materials, on which the conversion of light into an electrical signal (photodetectors) and vice versa (LEDs) is based, two-dimensional materials such as graphene, perovskites, transition metal dichalcogenides (TMDs), black phosphorus (BP), ternary compounds, carbon nanotubes, and topological insulators have recently begun to be widely introduced into optoelectronic devices. With their help and through heterojunctions based on them, many complementary properties and unique characteristics have been demonstrated. The latter are ensured, among other things, by wide variations in the electronic properties of new materials, from dielectric, such as in h-BN, semiconductors with different bandgaps (BP, CNT, and TMD), and semi-metals (graphene and WTe₂) to materials with metallic conductivity (CNT and CrI₃). This creates fundamentally new possibilities for application in various fields of optoelectronics, including photovoltaics, various photothermal detectors, and nanophotonics.

Of particular note is the growing interest in combining new materials and traditional optoelectronic semiconductors, such as silicon or gallium arsenide, to form heterojunctions. It has been demonstrated that such heterojunctions have excellent characteristics over a wide spectrum range, from UV to IR, and provide ultrafast charge carrier mobility and the ability to process and transform information at frequencies above GHz, up to the THz band.

Finally, an important factor is the compatibility of such structures with traditional semiconductor technology, which opens up new prospects for the formation of new-generation semiconductor photonic-integrated circuits.

Despite the initial promising results, much remains to be achieved in terms of understanding the mechanisms of current transport in thin-film materials under the influence of electrical and light signals, alongside the influence of interface states on optoelectronic parameters, and identifying ways to improve the performance of optoelectronic devices based on new thin-film materials and structures that will make them competitive with optoelectronic devices based on traditional materials.

This Special Issue is focused on all types of thin-film materials and the heterostructures based on them, tackling (but not limited to) the following topics:

• Fabrication processes for thin films and thin-film-based heterostructures for application in optoelectronics;
• Properties of thin films for optoelectronic applications;
• Properties of thin-film-based heterostructures for optoelectronic applications;
• Theoretical modeling of materials, interfaces, and low-dimensional properties for optoelectronic applications;
• Terahertz detector and terahertz generation;
• Metamaterials for optoelectronic applications.

Prof. Dr. Serghej Prischepa
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• thin films
• low-dimensional materials
• optoelectronics
• heterostructures
• terahertz waves
• interface states