National
CERBERUS – Farebné centrá v diamante – korelácia medzi atómovou štruktúrou a optoelektronickými vlastnosťami | |
Colour centres in diamond – correlation between atomic structure and opto-electronic properties | |
Program: | SRDA |
Project leader: | Ing. Varga Marian, PhD. |
Annotation: | The subject of the project is in the field of quantum technologies. We will prepare and characterize optically -activedefects in diamonds and correlate the atomic structures with optical properties to be used for quantum applicati ons.For a wide range of dopant concentrations, we will identify the dopant distributions and study the evolution ofdopants’ configuration in-situ, during thermal annealing, using atomic-resolution microscopy and spectroscopytechniques. We will further study the effect of annealing on the opto-electronic properties by measuringphotoluminescence, photocurrent and electroluminescence for the same set of samples. Graphene transparentelectrodes on a diamond surface will be fabricated for phototransport measurements. Diamond-based hybrid p-i-ndiodes will be prepared for electroluminescence measurements. We will focus on finding a correlation between theatomic structure and the opto-electronic properties of differently doped diamonds. This will contribute to theunderstanding of the fundamental relationship needed to efficiently design optically -active elements for diamondquantum devices. |
Duration: | 1.9.2024 – 31.12.2027 |
Transit2D – Tranzistory na báze 2D kovových chalkogenidov pripravených teplom podporovanou konverziou | |
Transistors based on 2D Metal Chalcogenides Grown via Thermally Assisted Conversion | |
Program: | SRDA |
Project leader: | Ing. Ťapajna Milan, PhD. |
Annotation: | 2D materials can form one-atom-thick sheets with extraordinary properties. One of the most promising classes of2D materials is the transition metal dichalcogenides (TMDs). The transition from an indirect to a direct bandgap,when the bulk materials is thinned down to a monolayer, results in unique electrical and optical properties of 2DTMDs. Post-transition metal chalcogenides (PTMCs) represents another interesting group of 2D materials. Thesematerials have wide band gap and, depending on the structure of the material, show anisotropic electrical andoptical properties. The aim of this project is the fabrication of field-effect transistors with metal-oxide-semiconductorgate (MOSFETs) based on selected TMDs and PTMCs compounds and detail analysis of their transport properties.We will focus on large-area few-layer PtSe2 and GaS/GaSe films grown by thermal assisted conversion, i.e.sulfurization and selenization. Based on the existing experiences, structural, chemical and electrical properties ofhorizontally-aligned PtSe2 films prepared by selenization will be optimized, targeting mobilities similar to thoseprepared by mechanical exfoliation. Then, MOSFET technology using both, top-gate as well as bottom-gateapproach will be developed and optimized. Atomic layer deposition and metal-oxide chemical vapor deposition(MOCVD) will be employed for gate oxide growth. GaS/GaSe few-layer films will be prepared by chalcogenization |
Duration: | 1.7.2022 – 30.6.2026 |
TMD2DCOR – Metalické 2D dichalkogenidy prechodných kovov: príprava, štúdium vlastností a korelované stavy | |
Fabrication, physics and correlated states in metallic 2D transition metal dichalcogenides | |
Program: | SRDA |
Project leader: | Dr. rer. nat. Hulman Martin |
Annotation: | The discovery of graphene in 2004 has brought a massive interest of scientists active in condensed-matter physicson research of 2D materials. Even though these materials have a long history starting already in the twenties of the20th century, the past years have seen an intensive renascence of interest in 2D materials. Ultra-thin samples ofmany 2D materials have been successfully prepared with electronic properties that may exhibit correlatedelectronic phenomena such as charge density waves and superconductivity. One of the well-studied families of the2D materials are transition metal dichalcogenides (TMDs). TMDs consist of hexagonal layers of metal atomssandwiched between two layers of chalcogen atoms with a MX2 stoichiometry.In this project, we focus on those materials from the TMD family that exhibit strongly correlated electronic states:NbSe2, TiSe2, TaS2, TaSe2 and PtSe2. The goal of the project is to prepare ultrathin (≤ 10 nm) layers and bulksamples and characterise them thoroughly in terms of the thickness, crystallinity, homogeneity, optical andelectronic properties. A special attention will be paid to charge density wave states and superconductivity in thesematerials and how they evolve with the sample thickness, doping, external electric and magnetic fields and detailsof the growth process.The scientific program also aims at preparing heterostructures built up of these materials as well as hybrid systemscombining TMDs with other materials. This research also includes a detailed characterisation of heterostructures toprovide a feedback to optimise the growth process. |
Duration: | 1.7.2020 – 30.6.2023 |