2022-10-24 アルゴンヌ国立研究所(ANL)
この研究成果は、量子コンピュータから家電製品に至るまで、将来的に重要な材料の原子スケールでの操作に関する研究に新たな窓を開くものである。
レアアースは、携帯電話やハイビジョンテレビなどのハイテク機器に不可欠な物質で。今回、正負の電荷を持つ希土類錯体を金属表面に初めて形成し、その回転を原子レベルで制御することに成功した。
実験は、アルゴンヌとオハイオ大学の2つの低温走査トンネル顕微鏡（STM）システムを用いて行われた。STMの実験環境は、超高真空で約5度K（華氏-450度）の温度が必要である。試料の分子サイズは2ナノメートル程度。
＜関連情報＞
- https://www.ohio.edu/news/2022/10/team-physicists-chemists-demonstrates-atomic-level-control-rare-earth-molecule
- https://www.nature.com/articles/s41467-022-33897-3
金属表面上の荷電希土類錯体における回転ダイナミクスの原子レベルの精密制御 Atomically precise control of rotational dynamics in charged rare-earth complexes on a metal surface
Tolulope Michael Ajayi,Vijay Singh,Kyaw Zin Latt,Sanjoy Sarkar,Xinyue Cheng,Sineth Premarathna,Naveen K. Dandu,Shaoze Wang,Fahimeh Movahedifar,Sarah Wieghold,Nozomi Shirato,Volker Rose,Larry A. Curtiss,Anh T. Ngo,Eric Masson & Saw Wai Hla
Nature Communications Published:22 October 2022
DOI:https://doi.org/10.1038/s41467-022-33897-3
Abstract
Complexes containing rare-earth ions attract great attention for their technological applications ranging from spintronic devices to quantum information science. While charged rare-earth coordination complexes are ubiquitous in solution, they are challenging to form on materials surfaces that would allow investigations for potential solid-state applications. Here we report formation and atomically precise manipulation of rare-earth complexes on a gold surface. Although they are composed of multiple units held together by electrostatic interactions, the entire complex rotates as a single unit when electrical energy is supplied from a scanning tunneling microscope tip. Despite the hexagonal symmetry of the gold surface, a counterion at the side of the complex guides precise three-fold rotations and 100% control of their rotational directions is achieved using a negative electric field from the scanning probe tip. This work demonstrates that counterions can be used to control dynamics of rare-earth complexes on materials surfaces for quantum and nanomechanical applications.
