Highly Tunable Magnetic Phases in Transition-Metal Dichalcogenide Fe1/3+δNbS2

Published

April 5, 2022

Author(s)

Shan Wu, Zhijun Xu, Shannon Haley, Sophie Weber, Arani Acharya, Eran Maniv, Yiming Qiu, A. A. Aczel, Nicholas S. Settineri, Jeffrey Neaton, James Analytis, Robert Birgeneau

Abstract

Layered transition metal dichalcogenides (TMDCs) host a plethora of interesting physical phenomena ranging from charge order to superconductivity. By introducing magnetic ions into 2H-NbS₂, the material forms a family of magnetic intercalated TMDCs T_xNbS₂ (T = 3d transition metal). Recently, Fe_1/3+δNbS₂ has been found to possess intriguing resistance switching and magnetic memory effects coupled to the Neel temperature of TN ∼ 45 K [1, 2]. We present comprehensive single crystal neutron diffraction measurements on under-intercalated (δ ∼ −0.01), stoichiometric, and over-intercalated (δ ∼ 0.01) samples. Magnetic defects are usually considered to suppress magnetic correlations and, concomitantly, transition temperatures. Instead, we observe highly tunable magnetic long-ranged states as the Fe concentration is varied from under-intercalated to over-intercalated, that is from Fe vacancies to Fe interstitials. The under- and over- intercalated samples reveal distinct antiferromagnetic stripe and zig-zag orders, associated with wave vectors k₁ = (0.5, 0, 0) and k₂ = (0.25, 0.5, 0), respectively. The stoichiometric sample shows two successive magnetic phase transitions for these two wave vectors with an unusual rise-and-fall feature in the intensities connected to k1. We ascribe this sensitive tunability to the competing next nearest neighbor exchange interactions and the oscillatory nature of the Ruderman-Kittel-Kasuya-Yosida (RKKY) mechanism. We discuss experimental observations that relate to the observed intriguing switching resistance behaviors. Our discovery of a magnetic defect tuning of the magnetic structure in bulk crystals Fe_1/3+δNbS₂ provides a possible new avenue to implement controllable antiferromagnetic spintronic devices.

Citation

Physical Review X

Volume

12

Issue

2

Pub Type

Journals

Keywords

neutron diffraction, magnetic defect tuning, transition metal dichalcogenide

Citation

Wu, S. , Xu, Z. , Haley, S. , Weber, S. , Acharya, A. , Maniv, E. , Qiu, Y. , Aczel, A. , Settineri, N. , Neaton, J. , Analytis, J. and Birgeneau, R. (2022), Highly Tunable Magnetic Phases in Transition-Metal Dichalcogenide Fe_1/3+δNbS₂, Physical Review X (Accessed April 19, 2024)