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-TA2 (T=Nb, Ta; A=S, Se), the material forms a family of magnetic intercalated TMDCs MxTA2 (M=3d transition metal). Recently, Fe1/3+δNbS2 has been found to possess intriguing resistance switching and magnetic memory effects coupled to the Néel temperature of TN∼45 K [Maniv et al., Nat. Phys. 17, 525 (2021)NPAHAX1745-247310.1038/s41567-020-01123-w; Sci. Adv. 7, eabd8452 (2021)SACDAF2375-254810.1126/sciadv.abd8452]. We present comprehensive single crystal neutron diffraction measurements on underintercalated (δ∼-0.01), stoichiometric, and overintercalated (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 underintercalated to overintercalated, that is, from Fe vacancies to Fe interstitials. The under- and overintercalated samples reveal distinct antiferromagnetic stripe and zigzag 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 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 Fe1/3+δNbS2 provides a possible new avenue to implement controllable antiferromagnetic spintronic devices.
| Original language | English |
|---|---|
| Article number | 021003 |
| Journal | Physical Review X |
| Volume | 12 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jun 2022 |
Funding
The authors would like to thank Edith Bourret-Courchesne, Didier Perrodin, Drew Onken, Peter Ercius, Rammamoorthy Ramesh, Yu He, Xiang Chen, Zhentao Wang, and Zhenglu Li for help and fruitful discussions. This work is partially funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division under Contract No. DE-AC02-05-CH11231 within the Quantum Materials Program (KC2202). The work of S. C. H., E. M., S. F. W., J. G. A., and J. B. N. was supported by the Center for Novel Pathways to Quantum Coherence in Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy, Director, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-05CH11231. Access to MACS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249. A portion of this research used resources at the High Flux Isotope Reactor, a U.S. DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.
| Funders | Funder number |
|---|---|
| National Science Foundation | DMR-1508249 |
| U.S. Department of Energy | |
| National Institute of Standards and Technology | |
| Office of Science | |
| Basic Energy Sciences | |
| Division of Materials Sciences and Engineering | DE-AC02-05-CH11231, KC2202 |