Out-of-plane easy-axis in thin films of diluted magnetic semiconductor Ba1−xKx(Zn1−yMny)2As2

Abstract

Single-phased, single-oriented thin films of Mn-doped ZnAs-based diluted magnetic semiconductor (DMS) Ba1−xKx(Zn1−yMny)2As2 (x = 0.03, 0.08; y = 0.15) have been deposited on Si, SrTiO3, LaAlO3, (La,Sr)(Al,Ta)O3, and MgAl2O4 substrates, respectively. Utilizing a combined synthesis and characterization system excluding the air and further optimizing the deposition parameters, high-quality thin films could be obtained and be measured showing that they can keep inactive-in-air up to more than 90 hours characterized by electrical transport measurements. In comparison with films of x = 0.03 which possess relatively higher resistivity, weaker magnetic performances, and larger energy gap, thin films of x = 0.08 show better electrical and magnetic performances. Strong magnetic anisotropy was found in films of x = 0.08 grown on (La,Sr)(Al,Ta)O3 substrate with their magnetic polarization aligned almost solely on the film growth direction.

Anisotropic Spin Distribution and Perpendicular Magnetic Anisotropy in a Layered Ferromagnetic Semiconductor (Ba,K)(Zn,Mn)2As2

“…These values give an anisotropy field μ 0 H K = 2K U /M sat of 0.85 ± 0.07 T. A positive value of K U means that the easy axis is along the c-axis, which is consistent with a previous study. 17 The obtained m Mn of 0.60 μ B at 20 K is also consistent with a previous study's 6 saturation magnetization (not shown here) but significantly smaller than that of (Ga,Mn)As, 2−4 μ B . 34,35 The cause of the reduction was theoretically attributed to the preferential formation of antiferromagnetically coupled nearest-neighbor Mn pairs 15 but should be clarified experimentally in future studies, for example, by performing XMCD measurements at various temperatures and magnetic fields.…”

“…In fact, large perpendicular magnetic anisotropy, where the magnetic easy axis is along the c-axis, was observed by SQUID measurements. 6,17 Perpendicular magnetic anisotropy is useful for future magnetic memory applications because it can lead to a high bit density and reduce the critical current density for magnetization switching. 18 In general, magnetocrystalline anisotropy would not appear from the Mn 2+ high-spin state ( 6 A 1 ) because of the lack of an orbital magnetic moment.…”

Anisotropic spin distribution and perpendicular magnetic anisotropy in the layered ferromagnetic semiconductor (Ba,K)(Zn,Mn)$_{2}$As$_{2}$

“…J/m 3 and the saturation magnetization per Mn atom m Mn = 0.60 ± 0.03 µ B . These values give the anisotropy field 2K U /M sat of 0.85 ± 0.07 T. The positive value of K U means that the easy axis is along the c-axis, being consistent with the previous study [17]. The obtained m Mn of 0.60 µ B at 20 K is by far smaller than those of (Ga,Mn)As of 4.5 µ B [4].…”

“…1a), sizable magnetic anisotropy would be expected. In fact, large perpendicular magnetic anisotropy (PMA), where the magnetic easy axis is along the c-axis, was observed by SQUID measurements [6,17], which is useful for future magnetic-memory applications. In general, magneto-crystalline anisotropy would not appear from the Mn 2+ high-spin state ( 6 A 1 ) because of the lack of orbital magnetic moment.…”

Anomalous critical point behavior in dilute magnetic semiconductor (Ca,Na)(Zn,Yu1, Liu2, Zhao3 et al. 2020Phys. Rev. Materials4160View full textAdd to dashboardCite

“…Recently a new class of DMS materials has been discoverede.g., Li 1+x (Zn,Mn)As, termed "111-type", and (Ba,K)(Zn,Mn) 2 As 2 , termed "122"in which carrier doping and spin doping are independent from each other, thus overcoming the difficulty just described [15][16][17][18][19][20][21]. For example, in (Ba,K)(Zn,Mn) 2 As 2 the isovalent substitution of Mn 2+ for Zn 2+ enables one to achieve high-Mn solubility (up to ~15% or more) in thermodynamic equilibrium, while substitution of K + for Ba 2+ produces charge carriers (holes) [22,23].…”