Supramolecular Approaches to Novel Physical scenarios in Hybrid van der Waals Heterostructures and Organic Semiconductors

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My research program investigates charge and spin transport of both molecular and 2D materials in devices with special focus on the effects arising from the supramolecular control of hetero-interfaces i.e. interfaces such as metal/semiconductor, dielectric/semiconductor or molecular non-covalent lattices over 2D covalently bonded (semi)conductors. Interfaces are a key element in my research program because they impact directly (i) conductivity, (ii) local band shape, (iii) charge and spin transport (iv) optical properties and, ultimately the (v) device physics in the class of materials this research program will be focusing on. Controlling such interfaces can give rise to novel and exciting physical scenarios. My research program focuses on: (1) Hybrid van der Waals heterostructures formed by 2D supramolecular lattices (SLs) over 2D materials such as graphene or transition metals dichalcogenides (TMDCs). In contrast with the recently suggested van der Waals heterostructures formed by multilayers of covalently-bonded 2D materials held together by weak interactions, within my research program I will explore new physical scenarios arising in hybrid systems formed by two-dimensional SLs over graphene or TMDCs. Of particular interest will be the effect of SLs in generating periodic potentials over graphene and TMDCs because such periodic potentials can be pre-programmed by molecular design and controlled with atomic precision. Tailoring such periodic potentials is novel and is currently a hot topic in 2D materials Physics. Furthermore, SLs containing molecules bearing heavy atoms affecting the mesoscopic characteristics of graphene will be studied by electrical characterization at low temperature and high magnetic fields, to explore the effects of superimposed SLs on quantum fingerprints of graphene and TMDCs such as Quantum Hall, Shubnikov-de Haas oscillations and weak (anti)localization. (2) Understanding and controlling the spin-mixing rules and magnetoresistance in supramolecularly assembled organic semiconductors by studying different molecular systems and supramolecular architectures. In particular, we will focus on understanding the relationship between bipolaron formation mechanism, molecular design and supramolecular architectures while measuring the magnetoresistance in polymer films realized through layer-by-layer vertical structures where the effect of the system dimensionality from 2D (single monolayer) up to 3D (multilayered film) will be explored at low temperature (down to 4 K) and high magnetic fields (up to 7 T). Furthermore, unraveling the role of the intrachain vs. interchain hopping rate in quasi-1D semiconducting wires and its related effect on inducing spin blockade in such supramolecular architectures will be investigated.