Twisted MoSe₂ Homobilayer Behaving as a Heterobilayer

Heterostructures (HSs) formed by the transition-metal dichalcogenides (TMDCs) materials have shown great promise in next-generation optoelectronic and photonic applications. An artificially twisted HS, allows us to manipulate the optical, and electronic properties. In this talk, I introduce our latest work [1] on the understanding of the complex energy transfer (ET) process governed by the dipolar interaction in a twisted molybdenum diselenide (MoSe₂) homobilayer <i>without</i> any charge-blocking interlayer, <i>i.e.</i>, in atomically closed proximity. We fabricated an unconventional homobilayer (<i>i.e.</i>, HS) with a large twist angle by combining the chemical vapor deposition (CVD) and mechanical exfoliation (Exf.) techniques to fully exploit the lattice parameters mismatch and indirect/direct (CVD/Exf.) bandgap nature. This effectively weaken the charge transfer (CT) process and allows the ET process to take over the carrier recombination channels. We utilize a series of optical and electron spectroscopy techniques complementing by the density functional theory calculations, to describe a massive photoluminescence enhancement from the HS area due to an efficient ET process. Our results show that the electronically decoupled MoSe₂ homobilayer is coupled by the ET process, mimicking a 'true' heterobilayer nature.<br/><br/>References:<br/>[1] A. Karmakar, A. Al-Mahboob, N. Zawadzka, M. Raczynski, W. Yang, M. Arfaoui, Gayatri, J. Kucharek, J. T. Sadowski, H. S. Shin, A. Babinski, W. Pacuski, T. Kazimierczuk, M. R Molas<i>, </i>''Twisted MoSe₂ Homobilayer Behaving as a <i>Heterobilayer</i>'', <i>arXiv:2404.15542v2</i> <i>(under review)</i>.