A recent study published in Nature Communications demonstrates precise control over electron spatial arrangement in two directions simultaneously—without any applied voltage—through interface engineering between semimetal bismuth (Bi) thin films and two-dimensional semiconductor MoS₂.
Researchers found that in the horizontal direction, the Moiré potential generated by small-angle twisted bilayer MoS₂ confines electrons to specific sites; in the vertical direction, tuning the bismuth film thickness modulates the electron effective mass, enabling switching between two distinct configurations—thinner films favor electron clustering into a trimer (molecular-like bonding) arrangement, while thicker films drive electrons apart into a periodic Kagome-like configuration.
Requiring no external voltage to induce electron confinement, this material system offers a critical foundation for developing charge qubits and ultra-low-power devices, potentially opening new design pathways for next-generation quantum computing and energy-efficient semiconductor chips.
"Bidirectional, gate-free manipulation of quantum electronic states offers a materials foundation for next-generation quantum computing and energy-efficient semiconductor technologies," says co-corresponding author Prof. Ya-Ping Chiu.
In this work, the team of Distinguished Professor Ya-Ping Chiu in the Department of Physics at National Taiwan University was responsible for the core atomic-scale experimental measurements and analysis.
Director and Distinguished Research Fellow Ching-Ming Wei of the Institute of Atomic and Molecular Sciences, Academia Sinica, together with the team of Professor Jyh-Pin Chou of the Graduate School of Advanced Technology, National Taiwan University, provided crucial support with theoretical calculations. The R&D team at Taiwan Semiconductor Manufacturing Company (TSMC) supplied high-quality semiconductor samples.
Provided by National Taiwan University