title: AC driven magnetic domain quantification with 5 nm resolution.
abstract: As the magnetic storage density increases in commercial products, e.g. the hard disc drives, a full understanding of dynamic magnetism in nanometer resolution underpins the development of next-generation products. Magnetic force microscopy (MFM) is well suited to exploring ferromagnetic domain structures. However, atomic resolution cannot be achieved because data acquisition involves the sensing of long-range magnetostatic forces between tip and sample. Moreover, the dynamic magnetism cannot be characterized because MFM is only sensitive to the static magnetic fields. Here, we develop a side-band magnetic force microscopy (MFM) to locally observe the alternating magnetic fields in nanometer length scales at an operating distance of 1 nm. Variations in alternating magnetic fields and their relating time-variable magnetic domain reversals have been demonstrated by the side-band MFM. The magnetic domain wall motions, relating to the periodical rotation of sample magnetization, are quantified via micromagnetics. Based on the side-band MFM, the magnetic moment can be determined locally in a volume as small as 5 nanometers. The present technique can be applied to investigate the microscopic magnetic domain structures in a variety of magnetic materials, and allows a wide range of future applications, for example, in data storage and biomedicine.
authors.affiliation: Liaoning Key Lab of Optoelectronic Films & Materials, School of Physics and Materials Engineering, Dalian Nationalities University, Dalian, 116600, China.
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.affiliation: Liaoning Key Lab of Optoelectronic Films & Materials, School of Physics and Materials Engineering, Dalian Nationalities University, Dalian, 116600, China.
authors.forename: Dapeng
authors.initials: D
authors.lastname: Dong
authors.affiliation: Liaoning Key Lab of Optoelectronic Films & Materials, School of Physics and Materials Engineering, Dalian Nationalities University, Dalian, 116600, China.
authors.forename: Dongping
authors.initials: D
authors.lastname: Liu
authors.affiliation: 1] Venture Business Laboratory, Akita University, Gakuen Machi 1-1, Tegata, Akita, 010-8502, Japan [2].
authors.forename: H
authors.initials: H
authors.lastname: Saito
authors.affiliation: Venture Business Laboratory, Akita University, Gakuen Machi 1-1, Tegata, Akita, 010-8502, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ishio