Ferromagnetic 2/1 quasicrystal approximants
Abstract
The existence of various magnetic orders has recently been established in the Tsai-type 1/1 approximant Au-Al-Gd by variation of the electron-per-atom (e/a) ratio [Ishikawa et al. Phys. Rev. B 98, 220403(R) (2018), 10.1103/PhysRevB.98.220403]. Here, we report ferromagnetic (FM) 2/1 quasicrystal approximants and show that the magnetic order of higher-order approximants can be tailored starting from known magnetic 1/1 approximants. The (Au,Cu)-(Al,In)-R (R =Gd ,Tb )2 /1 approximants are synthesized by the simultaneous substitution of isovalent elements Cu and In for Au and Al, respectively, to the FM Au-Al-R (R =Gd ,Tb )1 /1 approximants with e /a =1.74 . Both the (Au,Cu)-(Al,In)-R (R =Gd ,Tb )2 /1 approximants exhibit a FM transition at significantly high Curie temperatures of TC=30.0 and 15.3 K, respectively. Therefore, this method of isovalent substitution will also enable the realization of a variety of magnetic orders for the 2/1 approximant by variation of the e/a ratio. Such isovalent substitution may also stabilize magnetic quasicrystals for a given e/a ratio, which would lead to the realization of the long-range magnetic order in quasicrystals.
- Publication:
-
Physical Review B
- Pub Date:
- May 2020
- DOI:
- 10.1103/PhysRevB.101.180405
- Bibcode:
- 2020PhRvB.101r0405I