Magneto-transport properties of the off-stoichiometric Co_2MnAl film epitaxially grown on GaAs(001)
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摘要
We have investigated the magneto-transport properties of an off-stoichiometric full-Heusler alloy Co_2MnAl single-crystalline film. The Co_(1.65)Mn_(1.35)Al(CMA) film epitaxially grown on Ⅲ–Ⅴ semiconductor GaAs substrate exhibits perpendicular magnetic anisotropy. The resistivity of the CMA film increases with the temperature T decreasing from 300 to 5 K, showing a semiconducting-like transport behavior. Different activation energies are found in three temperature regions with transition temperatures of 35 and 110 K. In the meanwhile, the remanent magnetization can be described by T~(3/2) and T~2 laws in the corresponding medium and high T ranges, respectively. The transition at around 110 K could be attributed to the ferromagnetism evolving from localized to itinerant state. The Curie temperature of the CMA film is estimated to be ～640 K. The intrinsic anomalous Hall conductivity of ～55 Ω~(-1) cm~(-1) is obtained, which is almost twenty times smaller than that of Co_2MnAl.
We have investigated the magneto-transport properties of an off-stoichiometric full-Heusler alloy Co_2MnAl single-crystalline film. The Co_(1.65)Mn_(1.35)Al(CMA) film epitaxially grown on Ⅲ–Ⅴ semiconductor GaAs substrate exhibits perpendicular magnetic anisotropy. The resistivity of the CMA film increases with the temperature T decreasing from 300 to 5 K, showing a semiconducting-like transport behavior. Different activation energies are found in three temperature regions with transition temperatures of 35 and 110 K. In the meanwhile, the remanent magnetization can be described by T~(3/2) and T~2 laws in the corresponding medium and high T ranges, respectively. The transition at around 110 K could be attributed to the ferromagnetism evolving from localized to itinerant state. The Curie temperature of the CMA film is estimated to be ～640 K. The intrinsic anomalous Hall conductivity of ～55 Ω~(-1) cm~(-1) is obtained, which is almost twenty times smaller than that of Co_2MnAl.
We have investigated the magneto-transport properties of an off-stoichiometric full-Heusler alloy Co_2MnAl single-crystalline film. The Co_(1.65)Mn_(1.35)Al(CMA) film epitaxially grown on Ⅲ–Ⅴ semiconductor GaAs substrate exhibits perpendicular magnetic anisotropy. The resistivity of the CMA film increases with the temperature T decreasing from 300 to 5 K, showing a semiconducting-like transport behavior. Different activation energies are found in three temperature regions with transition temperatures of 35 and 110 K. In the meanwhile, the remanent magnetization can be described by T~(3/2) and T~2 laws in the corresponding medium and high T ranges, respectively. The transition at around 110 K could be attributed to the ferromagnetism evolving from localized to itinerant state. The Curie temperature of the CMA film is estimated to be ～640 K. The intrinsic anomalous Hall conductivity of ～55 Ω~(-1) cm~(-1) is obtained, which is almost twenty times smaller than that of Co_2MnAl.
引文
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[2]Trudel S, Gaier O, Hamrle J, et al. Magnetic anisotropy, exchange and damping in cobalt-based full-Heusler compounds:an experimental review. J Phys D, 2010, 43(19), 193001
[3]Wollmann L, Nayak A K, Parkin S S P, et al. Heusler 4.0:tunable materials. Ann Rev Mater Res, 2017, 47, 247
[4]Nayak A K, Nicklas M, Chadov S, et al. Design of compensated ferrimagnetic Heusler alloys for giant tunable exchange bias. Nat Mater, 2015, 14(7), 679
[5]Gueye M, Wague B M, Zighem F, et al. Bending strain-tunable magnetic anisotropy in Co2FeAl Heusler thin film on Kapton. Appl Phys Lett, 2014, 105(6), 062409
[6]Zhang B, Wang H L, Cao J, et al. Control of magnetic anisotropy in epitaxial Co2MnAl thin films through piezo-voltage-induced strain. J Appl Phys, 2019, 125(8), 082503
[7]Picozzi S, Continenza A, Freeman A J. Co2MnX(X=Si, Ge, Sn)Heusler compounds:An ab initio study of their structural, electronic, and magnetic properties at zero and elevated pressure.Phys Rev B, 2002, 66(9), 094421
[8]Ouardi S, Fecher G H, Felser C, et al. Realization of spin gapless semiconductors:The Heusler compound Mn2CoAl. Phys Rev Lett,2013, 110(10), 100401
[9]Jamer M E, Assaf B A, Devakul T, et al. Magnetic and transport properties of Mn2CoAl oriented films. Appl Phys Lett, 2013,103(14), 142403
[10]Xu G Z, Du Y, Zhang X M, et al. Magneto-transport properties of oriented Mn2CoAl films sputtered on thermally oxidized Si substrates. Appl Phys Lett, 2014, 104(24), 242408
[11]Feng Y, Zhou T, Chen X, et al. The effect of Mn content on magnetism and half-metallicity of off-stoichiometric Co2MnAl. JMMM,2015, 387, 118
[12]Zhang X, Cheng Y, Zhao W, et al. Exploring potentials of perpendicular magnetic anisotropy stt-mram for cache design. IEEE International Conference on Solid-State and Integrated Circuit Technology(ICSICT), 2014, 1
[13]Meng K K, Miao J, Xu X, et al. Thickness dependence of magnetic anisotropy and intrinsic anomalous Hall effect in epitaxial Co2MnAl film. Phys Lett A, 2017, 381(13), 1202
[14]Gofryk K, Kaczorowski D, Plackowski T, et al. Magnetic and transport properties of the rare-earth-based Heusler phases R Pd Z and R Pd 2 Z(Z=Sb, Bi). Phys Rev B, 2005, 72(9), 094409
[15]Raquet B, Viret M, Warin P, et al. Negative high field magnetoresistance in 3d ferromagnets. Physica B, 2001, 294, 102
[16]Hordequin C, Pierre J, Currat R. Magnetic excitations in the halfmetallic NiMnSb ferromagnet:From Heisenberg-type to itinerant behaviour. JMMM, 1996, 162(1), 75
[17]Du Y, Xu G Z, Zhang X M, et al. Crossover of magnetoresistance in the zero-gap half-metallic Heusler alloy Fe2CoSi. Europhys Lett,2013, 103(3), 37011
[18]Ishikawa Y, Shirane G, Tarvin J A, et al. Magnetic excitations in the weak itinerant ferromagnet MnSi. Phys Rev B, 1977, 16(11), 4956
[19]Wohlfarth E P. Very weak itinerant ferromagnets application to ZrZn2. J Appl Phys, 1968, 39(2), 106
[20]Nagaosa N, Sinova J, Onoda S, et al. Anomalous hall effect. Rev Modern Phys, 2010, 82(2), 1539
[21]Tian Y, Ye L, Jin X. Proper scaling of the anomalous Hall effect.Phys Rev Lett, 2009, 103(8), 087206
[2]Trudel S, Gaier O, Hamrle J, et al. Magnetic anisotropy, exchange and damping in cobalt-based full-Heusler compounds:an experimental review. J Phys D, 2010, 43(19), 193001
[3]Wollmann L, Nayak A K, Parkin S S P, et al. Heusler 4.0:tunable materials. Ann Rev Mater Res, 2017, 47, 247
[4]Nayak A K, Nicklas M, Chadov S, et al. Design of compensated ferrimagnetic Heusler alloys for giant tunable exchange bias. Nat Mater, 2015, 14(7), 679
[5]Gueye M, Wague B M, Zighem F, et al. Bending strain-tunable magnetic anisotropy in Co2FeAl Heusler thin film on Kapton. Appl Phys Lett, 2014, 105(6), 062409
[6]Zhang B, Wang H L, Cao J, et al. Control of magnetic anisotropy in epitaxial Co2MnAl thin films through piezo-voltage-induced strain. J Appl Phys, 2019, 125(8), 082503
[7]Picozzi S, Continenza A, Freeman A J. Co2MnX(X=Si, Ge, Sn)Heusler compounds:An ab initio study of their structural, electronic, and magnetic properties at zero and elevated pressure.Phys Rev B, 2002, 66(9), 094421
[8]Ouardi S, Fecher G H, Felser C, et al. Realization of spin gapless semiconductors:The Heusler compound Mn2CoAl. Phys Rev Lett,2013, 110(10), 100401
[9]Jamer M E, Assaf B A, Devakul T, et al. Magnetic and transport properties of Mn2CoAl oriented films. Appl Phys Lett, 2013,103(14), 142403
[10]Xu G Z, Du Y, Zhang X M, et al. Magneto-transport properties of oriented Mn2CoAl films sputtered on thermally oxidized Si substrates. Appl Phys Lett, 2014, 104(24), 242408
[11]Feng Y, Zhou T, Chen X, et al. The effect of Mn content on magnetism and half-metallicity of off-stoichiometric Co2MnAl. JMMM,2015, 387, 118
[12]Zhang X, Cheng Y, Zhao W, et al. Exploring potentials of perpendicular magnetic anisotropy stt-mram for cache design. IEEE International Conference on Solid-State and Integrated Circuit Technology(ICSICT), 2014, 1
[13]Meng K K, Miao J, Xu X, et al. Thickness dependence of magnetic anisotropy and intrinsic anomalous Hall effect in epitaxial Co2MnAl film. Phys Lett A, 2017, 381(13), 1202
[14]Gofryk K, Kaczorowski D, Plackowski T, et al. Magnetic and transport properties of the rare-earth-based Heusler phases R Pd Z and R Pd 2 Z(Z=Sb, Bi). Phys Rev B, 2005, 72(9), 094409
[15]Raquet B, Viret M, Warin P, et al. Negative high field magnetoresistance in 3d ferromagnets. Physica B, 2001, 294, 102
[16]Hordequin C, Pierre J, Currat R. Magnetic excitations in the halfmetallic NiMnSb ferromagnet:From Heisenberg-type to itinerant behaviour. JMMM, 1996, 162(1), 75
[17]Du Y, Xu G Z, Zhang X M, et al. Crossover of magnetoresistance in the zero-gap half-metallic Heusler alloy Fe2CoSi. Europhys Lett,2013, 103(3), 37011
[18]Ishikawa Y, Shirane G, Tarvin J A, et al. Magnetic excitations in the weak itinerant ferromagnet MnSi. Phys Rev B, 1977, 16(11), 4956
[19]Wohlfarth E P. Very weak itinerant ferromagnets application to ZrZn2. J Appl Phys, 1968, 39(2), 106
[20]Nagaosa N, Sinova J, Onoda S, et al. Anomalous hall effect. Rev Modern Phys, 2010, 82(2), 1539
[21]Tian Y, Ye L, Jin X. Proper scaling of the anomalous Hall effect.Phys Rev Lett, 2009, 103(8), 087206