Ultrathin Ferrimagnetic GdFeCo Films with Low Damping. (1st March 2022)

• Record Type: Journal Article
• Authors: Bainsla, Lakhan; Kumar, Akash; Awad, Ahmad A.; Wang, Chunlei; Zahedinejad, Mohammad; Behera, Nilamani; Fulara, Himanshu; Khymyn, Roman; Houshang, Afshin; Weissenrieder, Jonas; Åkerman, Johan
• Is Part Of: Advanced functional materials. Volume 32:Number 23(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-01
• Subjects: compensated ferrimagnets -- ferromagnetic resonance -- Gilbert damping constant -- spintronics -- tetrahertz oscillators; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202111693
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Ferromagnetic materials dominate as the magnetically active element in spintronic devices, but come with drawbacks such as large stray fields and low operational frequencies. Compensated ferrimagnets provide an alternative as they combine the ultrafast magnetization dynamics of antiferromagnets with a ferromagnet‐like spin‐orbit‐torque behavior. However, to use ferrimagnets in spintronic devices their advantageous properties must be retained also in ultrathin films ( t < 10 nm). In this study, ferrimagnetic Gd x (Fe87.5 Co12.5 )1− x thin films in the thickness range t = 2–20 nm are grown on high resistance Si(100) substrates and studied using broadband ferromagnetic resonance measurements at room temperature. By tuning their stoichiometry, a nearly compensated behavior is observed in 2 nm Gd x (Fe87.5 Co12.5 )1− x ultrathin films for the first time, with an effective magnetization of M e f f = 0.02 T and a low effective Gilbert damping constant of α = 0.0078, comparable to the lowest values reported so far in 30 nm films. These results show great promise for the development of ultrafast and energy efficient ferrimagnetic spintronic devices. Abstract : Compensated ferrimagnets are promising materials as they combine the ultrafast magnetization dynamics of antiferromagnets with a ferromagnet‐like spin‐orbit‐torque behavior. Compensated ferrimagnetic behavior with low Gilbert damping constant values is obtained in ultrathin films of GdFeCo, and these results show great promise for the development of ultrafast and energy efficient ferrimagnetic spintronic devices.