Prof. Maciej Wiesner, Institute of Physics, Faculty of Physics and Astronomy, AMU
Seminarium hybrydowe, sala Rady Dyscyplin (sala 16), 12.03.2026, 15:00
Title
Effects of Intercalation on electron and phonon transport in van der Waals crystals under extreme conditions
Abstract:
The presentation discusses the influence of intercalation on electron and phonon transport in van der Waals (vdW) crystals and their potential applications in nanoelectronics. It begins by explaining that the miniaturization of transistors is approaching fundamental physical limits, with channel lengths of only a few nanometers and extremely thin oxide layers, which makes the search for new materials essential for further technological development. Van der Waals materials, such as graphene and transition metal dichalcogenides (e.g., MoS₂), exhibit unique properties due to their layered structure. These materials allow the isolation of single atomic layers and the creation of artificial heterostructures with tunable electronic, optical, and thermal properties. Their two-dimensional confinement leads to strong transport anisotropy and the emergence of quantum effects that are not present in bulk materials. The work focuses on modifying interlayer interactions in vdW materials using three main approaches: hydrostatic pressure, applied electric fields, and intercalation, which involves inserting atoms or ions into the van der Waals gaps between layers. Intercalation can significantly influence material properties by changing the carrier concentration, shifting the Fermi level, and introducing new conduction pathways between layers. As a result, it can induce electronic phase transitions such as insulator-to-metal or even superconducting behavior, as well as alter phonon transport and thermal conductivity. Experimental examples include materials such as Bi₂Se₃, Bi₂Te₃, CrCl₃, and MoO₃. In these systems, intercalation leads to observable changes in band structure, photoluminescence, and electron–phonon coupling. Some experiments also reveal phenomena such as resistive switching and memory effects, which are important for future electronic devices. Overall, the results show that controlling interlayer interactions in van der Waals materials—especially through intercalation—is a promising strategy for designing new functional materials for next-generation nanoelectronic, photonic, spintronic, and quantum devices.