Antiferromagnetic fluctuations and orbital-selective Mott transition in the van der Waals ferromagnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mtext>Fe</mml:mtext><mml:mrow><mml:mn>3</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:msub><mml:mtext>GeTe</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>
Xiaojian Bai, Frank Lechermann, Yaohua Liu, Yongqiang Cheng, А. И. Колесников, Feng Ye, T. J. Williams, Songxue Chi, Tao Hong, G. E. Granroth, Andrew F. May, Stuart Calder
Abstract
Fe${}_{3\ensuremath{-}x}$GeTe${}_{2}$ is one of the most intensely studied quasi-two-dimensional layered materials of recent times. It can be exfoliated down to a monolayer and has promising applications in room-temperature magnetoelectronics. Here, the authors use neutron scattering and first-principle calculations to study its fundamental magnetic and electronic properties. A rare orbital selective Mott transition was identified that drives the emergence of antiferromagnetic fluctuations within the ferromagnetic order, opening a new avenue in understanding the coexistence of itinerant and local moments and the heavy-fermion physics in this 3$d$ electron system.