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Zhang KX, Xu H, Keum J, Wang X, Liu M, Chen Z. Unexpected versatile electrical transport behaviors of ferromagnetic nickel films. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:235801. [PMID: 38417165 DOI: 10.1088/1361-648x/ad2e25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 02/28/2024] [Indexed: 03/01/2024]
Abstract
Perpendicular magnetic anisotropy (PMA) of magnets is paramount for electrically controlled spintronics due to their intrinsic potentials for higher memory density, scalability, thermal stability and endurance, surpassing an in-plane magnetic anisotropy (IMA). Nickel film is a long-lived fundamental element ferromagnet, yet its electrical transport behavior associated with magnetism has not been comprehensively studied, hindering corresponding spintronic applications exploiting nickel-based compounds. Here, we systematically investigate the highly versatile magnetism and corresponding transport behavior of nickel films. As the thickness reduces within the general thickness regime of a magnet layer for a memory device, the hardness of nickel films' ferromagnetic loop of anomalous Hall effect increases and then decreases, reflecting the magnetic transitions from IMA to PMA and back to IMA. Additionally, the square ferromagnetic loop changes from a hard to a soft one at rising temperatures, indicating a shift from PMA to IMA. Furthermore, we observe a butterfly magnetoresistance resulting from the anisotropic magnetoresistance effect, which evolves in conjunction with the thickness and temperature-dependent magnetic transformations as a complementary support. Our findings unveil the rich magnetic dynamics and most importantly settle down the most useful guiding information for current-driven spintronic applications based on nickel film: The hysteresis loop is squarest for the ∼8 nm-thick nickel film, of highest hardness withRxyr/Rxys∼ 1 and minimumHs-Hc, up to 125 K; otherwise, extra care should be taken for a different thickness or at a higher temperature.
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Affiliation(s)
- Kai-Xuan Zhang
- Center for Quantum Materials, Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Hanshu Xu
- Department of Applied Physics, School of Biomedical Engineering, Anhui Medical University, Hefei 230032, People's Republic of China
| | - Jihoon Keum
- Center for Quantum Materials, Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Xiangqi Wang
- Jihua Laboratory Testing Center, Jihua Laboratory, Foshan 528000, People's Republic of China
| | - Meizhuang Liu
- School of Semiconductor Science and Technology, South China Normal University, Foshan 528225, People's Republic of China
| | - Zuxin Chen
- School of Semiconductor Science and Technology, South China Normal University, Foshan 528225, People's Republic of China
- Guangdong Provincial Key Laboratory of Chip and Integration Technology, Guangzhou 510631, People's Republic of China
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Xiao Z, Lo Conte R, Goiriena-Goikoetxea M, Chopdekar RV, Lambert CHA, Li X, N'Diaye AT, Shafer P, Tiwari S, Barra A, Chavez A, Mohanchandra KP, Carman GP, Wang KL, Salahuddin S, Arenholz E, Bokor J, Candler RN. Tunable Magnetoelastic Effects in Voltage-Controlled Exchange-Coupled Composite Multiferroic Microstructures. ACS APPLIED MATERIALS & INTERFACES 2020; 12:6752-6760. [PMID: 31927947 DOI: 10.1021/acsami.9b20876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The magnetoelectric properties of exchange-coupled Ni/CoFeB-based composite multiferroic microstructures are investigated. The strength and sign of the magnetoelastic effect are found to be strongly correlated with the ratio between the thicknesses of two magnetostrictive materials. In cases where the thickness ratio deviates significantly from one, the magnetoelastic behavior of the multiferroic microstructures is dominated by the thicker layer, which contributes more strongly to the observed magnetoelastic effect. More symmetric structures with a thickness ratio equal to one show an emergent interfacial behavior which cannot be accounted for simply by summing up the magnetoelastic effects occurring in the two constituent layers. This aspect is clearly visible in the case of ultrathin bilayers, where the exchange coupling drastically affects the magnetic behavior of the Ni layer, making the Ni/CoFeB bilayer a promising next-generation synthetic magnetic system entirely. This study demonstrates the richness and high tunability of composite multiferroic systems based on coupled magnetic bilayers compared to their single magnetic layer counterparts. Furthermore, because of the compatibility of CoFeB with present magnetic tunnel junction-based spintronic technologies, the reported findings are expected to be of great interest for the development of ultralow-power magnetoelectric memory devices.
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Affiliation(s)
- Z Xiao
- Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - R Lo Conte
- Department of Electrical Engineering and Computer Science , University of California, Berkeley , Berkeley 94720 , California , United States
| | - M Goiriena-Goikoetxea
- Department of Electrical Engineering and Computer Science , University of California, Berkeley , Berkeley 94720 , California , United States
- Department of Electricity and Electronics , University of the Basque Country , Leioa 48940 , Spain
| | - R V Chopdekar
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - C-H A Lambert
- Department of Electrical Engineering and Computer Science , University of California, Berkeley , Berkeley 94720 , California , United States
| | - X Li
- Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - A T N'Diaye
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - P Shafer
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - S Tiwari
- Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - A Barra
- Department of Mechanical and Aerospace Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - A Chavez
- Department of Mechanical and Aerospace Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - K P Mohanchandra
- Department of Mechanical and Aerospace Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - G P Carman
- Department of Mechanical and Aerospace Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - K L Wang
- Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
| | - S Salahuddin
- Department of Electrical Engineering and Computer Science , University of California, Berkeley , Berkeley 94720 , California , United States
| | - E Arenholz
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - J Bokor
- Department of Electrical Engineering and Computer Science , University of California, Berkeley , Berkeley 94720 , California , United States
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley 94720 , California , United States
| | - R N Candler
- Department of Electrical and Computer Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
- Department of Mechanical and Aerospace Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States
- California NanoSystems Institute , Los Angeles 90095 , California , United States
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Kumar P. Magnetic Behavior of Surface Nanostructured 50-nm Nickel Thin Films. NANOSCALE RESEARCH LETTERS 2010; 5:1596-1602. [PMID: 21076670 PMCID: PMC2956046 DOI: 10.1007/s11671-010-9682-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 06/30/2010] [Indexed: 05/30/2023]
Abstract
Thermally evaporated 50-nm nickel thin films coated on borosilicate glass substrates were nanostructured by excimer laser (0.5 J/cm(2), single shot), DC electric field (up to 2 kV/cm) and trench-template assisted technique. Nanoparticle arrays (anisotropic growth features) have been observed to form in the direction of electric field for DC electric field treatment case and ruptured thin film (isotropic growth features) growth for excimer laser treatment case. For trench-template assisted technique; nanowires (70-150 nm diameters) have grown along the length of trench template. Coercive field and saturation magnetization are observed to be strongly dependent on nanostructuring techniques.
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Affiliation(s)
- Prashant Kumar
- Chemistry and Physics of Materials Unit (CPMU), Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore, 560064, India
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