TY - JOUR
T1 - Thermal agitation of magnetization in CoCrPt perpendicular recording media
AU - Shimatsu, T.
AU - Uwazumi, H.
AU - Sakai, Y.
AU - Otsuki, A.
AU - Watanabe, I.
AU - Muraoka, H.
AU - Nakamura, Y.
N1 - Funding Information:
Manuscript received October 12, 2000. This work was supported in part by ASET and SRC. T. Shimatsu, I. Watanabe, H. Muraoka, and Y. Nakamura are with Research Institute of Electrical Communication, Tohoku University, Sendai, 980-8577, Japan (e-mail: shimatsu@riec.tohoku.ac.jp). H. Uwazumi, Y. Sakai, and A. Otsuki are with Fuji Electric Co., Ltd., Tsukama 4-18-1, Matsumoto, 390-0821, Japan (e-mail: uwazumi-hiroyuki@fu-jielectric.co.jp). Publisher Item Identifier S 0018-9464(01)06859-5.
PY - 2001/7
Y1 - 2001/7
N2 - Magnetic and structural properties of CoCrPt based perpendicular recording media required to achieve both high thermal stability and low-noise performance are discussed, based on experimental results obtained using a pulse magnetometer. Experimental and theoretical analysis reveal that for CoCrPt based media of 20 nm thickness having the thermal stability factor KuV/(kT) ≈ 80, the maximum achievable value of the ratio of remanence coercivity to anisotropy field of grains, Hr/Hk, is ∼0.35. Furthermore, if the strictest condition of demagnetizing factor, 4π, for perpendicular media is assumed, in order to realize a large squareness Mr/Ms of nearly 1.0, which is required to resist the thermal agitation effect, we find that the value of perpendicular magnetocrystalline anisotropy, Ku, has to be more than 3 times larger than 2πM82.
AB - Magnetic and structural properties of CoCrPt based perpendicular recording media required to achieve both high thermal stability and low-noise performance are discussed, based on experimental results obtained using a pulse magnetometer. Experimental and theoretical analysis reveal that for CoCrPt based media of 20 nm thickness having the thermal stability factor KuV/(kT) ≈ 80, the maximum achievable value of the ratio of remanence coercivity to anisotropy field of grains, Hr/Hk, is ∼0.35. Furthermore, if the strictest condition of demagnetizing factor, 4π, for perpendicular media is assumed, in order to realize a large squareness Mr/Ms of nearly 1.0, which is required to resist the thermal agitation effect, we find that the value of perpendicular magnetocrystalline anisotropy, Ku, has to be more than 3 times larger than 2πM82.
KW - Intergranular exchange coupling
KW - Low media noise
KW - Perpendicular recording media
KW - Pulse magnetometer
KW - Remanence coercivity
KW - Thermal agitation
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U2 - 10.1109/20.950902
DO - 10.1109/20.950902
M3 - Conference article
AN - SCOPUS:0035386793
SN - 0018-9464
VL - 37
SP - 1567
EP - 1569
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
IS - 4 I
T2 - 8th Joint Magnetism and Magnetic Materials -International Magnetic Conference- (MMM-Intermag)
Y2 - 7 January 2001 through 11 January 2001
ER -