http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Duy-Truong Quach,Tien-Dung Chu,Tuan-Son Nguyen,Thi-Thuy-Phuong Doan,Xuan-Tuyen Nguyen,이경민,정종렬,김남동,신현준,김동현 한국물리학회 2020 Current Applied Physics Vol.20 No.9
We have comprehensively investigated asymmetric magnetization reversal behaviors of (x-Å Co/7.7 Å Pt)5 multilayers (x = 3.1 and 4.7) with perpendicular magnetic anisotropy. Our direct observation of magnetic domain structures by means of magneto-optical microscopy reveals that the asymmetry arises both from nucleation and wall-motion processes. An asymmetric nucleation behavior is observed, which could be originated from the preexisting non-reversed domains which might have a reproducible or random spatial distribution, controllable by tuning the field profile. An asymmetric wall-motion behavior stemming from asymmetric stripe domain evolution is also observed.
Investigation of Microscopic Demagnetization Process Using Magneto-Optical Microscopy
Duy-Truong Quach,Sang-Hyuk Lee,Dong-Hyun Kim IEEE 2014 IEEE transactions on magnetics Vol.50 No.6
<P>Detailed demagnetization process depending on various external field profiles has been investigated using a magneto-optical Kerr/Faraday microscopy for a Co/Pt multilayer film with a perpendicular magnetic anisotropy. By quantitatively analyzing local magnetic domain structures, we propose that it is possible to define a parameter η, which represents how well the demagnetization has been carried out microscopically. The degree of demagnetization η, defined by a ratio between the final demagnetized image intensity and saturated image intensity, has been experimentally found to significantly reflect the microscopic demagnetization behavior. Dependences of η on the maximum amplitude, decreased step size, and effective sweeping rate of alternating demagnetizing field have been systematically investigated together with a direct microscopic observation of magnetic domain structures.</P>
Nanometer-scale local probing of X-ray absorption spectra of Co/Pt multilayer film
Quach, Duy-Truong,Pham, Duc-Thang,Handoko, Djati,Shim, Je-Ho,Eon Kim, Dong,Lee, Kyung-Min,Jeong, Jong-Ryul,Kim, Namdong,Shin, Hyun-Joon,Kim, Dong-Hyun Elsevier 2018 PHYSICA B-CONDENSED MATTER - Vol.532 No.-
<P><B>Abstract</B></P> <P>We report our local X-ray absorption spectra (XAS) measurement mapping for a Co/Pt multilayer using scanning transmission microscopy with 25-nm spatial resolution and 0.1-eV spectral resolution. We have systematically analyzed the two-dimensional XAS intensity variation over the corresponding magnetic domain patterns, revealing a XAS profile across the magnetic domain wall as well as the simultaneous high-throughput measurement of local XAS spectra.</P>
Microscopic Investigation of the Magnetic Saturation Process for Co/Pt Multilayers
Duy-Truong Quach,Dong-Hyun Kim,Kyung-Min Lee,정종율,Duc-Thang Pham 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.1
We have systematically investigated the magnetic saturation process for Co/Pt multilayers with perpendicular magnetic anisotropy by using the first-order reversal-curve (FORC) technique. We find that even for a field that apparently is higher than the major-loop saturation field, some microscopically not-yet-annihilated domains still remain. The true saturation on a microscopic scale field is found to be about 1.5 to 2.5 times greater than the macroscopicall-determined majorloop saturation field. Not-yet-annihilated domains are observed to be exponentially reduced with respect to the applied magnetic field.
Handoko, Djati,Duy-Truong Quach,Sang-Hyuk Lee,Kyung Min Lee,Jong-Ryul Jeong,Dong Seok Yang,Dong-Hyun Kim IEEE 2016 IEEE transactions on magnetics Vol.52 No.2
<P>We have discovered that there exist dynamic scaling behaviors for the nucleation and the saturation field in hysteresis loop of Co/Pt multilayer thin films. The dynamic hysteresis measurement was carried out with variation of sweeping rate of cycling fields, which reveals that not only the coercivity and the loop area, well known as the Steinmetz law, but also the nucleation and the saturation field exhibit similar scaling behaviors. We have systematically analyzed the scaling factor of nucleation, coercivity, and saturation phase with respect to the Co sublayer thickness. Local structural configuration depending on the Co sublayer thickness were examined by extended X-ray absorption fine structure, implying that damping parameter and interface effect modifies the coercivity and nucleation scaling factor but does not significantly induce the change in saturation scaling factors.</P>
Djati Handoko,Duy-Truong Quach,이상혁,심재호,김동현,이경민,정종율,김남동,신현준 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.11
We report our investigation on the magnetic-domain structure of a Co/Pt multilayer with perpendicular magnetic anisotropy under a horizontal in-plane field by using a high-resolution scanning transmission X-ray microscope (STXM) developed at Pohang Accelerator Laboratory. The ruggedshaped striped magnetic-domain structure that was initially formed under a field cycle along the out-of-the plane magnetic easy axis was found to be stretched and elongated along the direction of the horizontal in-plane field. As the in-plane field was strengthened, the striped pattern exhibited an anisotropic domain growth with further stretching and aligning, as well as with a modification of the magnetic-domain’s width.