Events

Abstract: With the development of advanced fabrication methods for 2D heterostructures, devices based on atomically thin semiconducting transition metal dichalcogenides (TMDs) are emerging as a promising platform for quantum information science. Semiconducting TMDs typically exhibit direct bandgaps, with optical properties dominated by many-body complexes. They hold potential for realizing qubits with long coherence times due to spin-valley locking. Various 2D heterostructures offer also possibilities to engineer long-lived optical complexes, such as interlayer excitons. These promising properties motivate our recent efforts to understand these materials [1-4].  
In this talk, I will present our theoretical investigation of an electrically tunable MoSe2/WSe2 heterostructure [5]. Van der Waals heterostructures offer the ability to tune electronic properties beyond their monolayer constituents. We begin by determining the electronic structure, finding a type-II band alignment with conduction band minima at the K and Q points and valence band maxima at the K and Γ points. We analyze the layer, spin, and orbital contributions in detail. Building on this, we develop a tight-binding model that captures the complexity of the interlayer interactions. We demonstrate that vertical gating enables control of valleys extrema. We further investigate laterally gated quantum dots, proposing a qutrit implementation in these systems.

 

[1] M. Bieniek, M. Korkusiński, L. Szulakowska, P. Potasz, I. Ozfidan, P. Hawrylak, „Band nesting, massive Dirac fermions, and valley Landé and Zeeman effects in transition metal dichalcogenides: A tight-binding model”, PRB 97, 085153 (2018),
[2] M. Bieniek, L. Szulakowska, P. Hawrylak, “Band nesting and exciton spectrum in monolayer MoS2”, PRB 101, 125423 (2020)
[3] Justin Boddison-Chouinard, Alex Bogan, Pedro Barrios, Jean Lapointe, Kenji Watanabe, Takashi Taniguchi, Jarosław Pawłowski, Daniel Miravet, Maciej Bieniek, Pawel Hawrylak, Adina Luican-Mayer, Louis Gaudreau, “Anomalous conductance quantization of a one-dimensional channel in monolayer WSe2”, npj 2D Materials and Applications 7, 50 (2023)
[4] J. Pawłowski, D. Miravet, M. Bieniek, M. Korkusiński, J. Boddison-Chouinard, L. Gaudreau, A. Luican-Mayer, P. Hawrylak, “Interacting holes in a gated WSe2 quantum channel: valley correlations and zigzag Wigner crystal”, PRB 110 (12), 125147 (2024)
[5] K. Sadecka, M. Bieniek, P. E. Faria Junior, A. Wojs, P. Hawrylak, J. Pawlowski, “Electrically tunable valley couplings in MoSe2/WSe2 heterostructure”, PRB 111 (11), 115421 (2025)