SPring-8, the large synchrotron radiation facility

Inquiry number

SOL-0000001034

Beamline

BL39XU (X-ray Absorption and Emission Spectroscopy)

Scientific keywords

A. Sample category	inorganic material
B. Sample category (detail)	magnetic material
C. Technique	absorption and its secondary process
D. Technique (detail)	XANES, MCD, LD
E. Particular condition	polarization (circular), high pressure (DAC), magnetic field (< 2 T), room temperature
F. Photon energy	X-ray (4-40 keV)
G. Target information	electronic state, spin/magnetism, phase transition

Industrial keywords

level 1---Application area	storage device
level 2---Target	HD,MO
level 3---Target (detail)	magnetic layer
level 4---Obtainable information	local structure, electronic state, magnetic moment, magnetic anisotropy
level 5---Technique	XAFS, XMCD

Classification

A80.14 magnetic materials, M40.30 XMCD

Body text

X-ray Magnetic Circular Dichroism (XMCD) is a unique technique to study electronic states for the specific element and its orbital. In addition, XMCD intensity is proportional to the magnitude of the sample magnetization.Using this technique, therefore, we can obtain the relative magnitude of the magnetic moment of the focusing magnetic atom asa function of temperature, magnetic field ,or pressure.3d transition elements (Cr-Cu), 4f rare-earth elements (La-Lu), and 5d transition elements (Hf-Pt, Au) in ferromagnetic materials can be investigated because circularly polarized X-rays in hard X-ray region (5-16 keV) are available at BL39XU of SPring-8.

The figure shows pressure dependence of XMCD intensity at the Fe K-edge (1s-4p)of Fe₄N. These data indicate the fact that Fe magnetic moments in Fe₄N vanish at 24 GPa although the ferromagnetic state is relatively stable because Fe atoms form a face-centered lattice.Moreover, this pressure-induced magnetic phase transition is a second-order phase transition because of no pressure hysteresis.

Fig. Pressure dependence of the XMCD intensity at the Fe K-edge in Fe₄N.

[ N. Ishimatsu, H. Maruyama, N. Kawamura, M. Suzuki, Y. Ohishi, M. Ito, S. Nasu, T. Kawakami and Osamu, Journal of the Physical Society of Japan 72, 2372-2376 (2003), Fig. 2,
©2003 The Japan Society of Applied Physics ]

Source of the figure

Original paper/Journal article

Journal title

N. Ishimatsu et al., J. Phys. Soc. Jpn. 72, 2372 (2003).

Figure No.

Fig. 2

Technique

XMCD spectrum is measured by monitoring the difference in X-ray absorption of the sample between for right- and left-circularly polarized X-rays, as a function of the X-ray energy. In particular, we can obtain the relative magnitude of the magnetic moments of the specified element individually in the compound composed by multiple magnetic atoms because the XMCD intensity is proportional to the magnitude of the sample magnetization. In this solution, the information about the pressure variation of Fe magnetic moments in Fe₄N can be obtained by measuring XMCD intensity dependent on pressure at the Fe K-edge.

Fig. Principle of X-ray magnetic circular dichroism (XMCD) measurement.

Source of the figure

Private communication/others

Description

鈴木基寛氏による作成

Required time for experimental setup

5 hour(s)

Instruments

Instrument	Purpose	Performance
Electromagnet and closed-cycle helium refrigerator	measurement of XMCD spectrum between room temperature and low temperature	maximum applied magnetic field of 2 T, temperature range of 20-300 K at sample position

References

Document name
N. Ishimatsu, Y. Ohishi, M. Suzuki, N. Kawamura, M. Ito, H. Maruyama, S. Nasu, T. Kawakami, and O. Shimomura, Nucl. Instrum. Methods Phys. Res. A 467-468, 1061 (2001).
N. Ishimatsu, H. Maruyama, N. Kawamura, M. Suzuki, Y. Ohishi, M. Ito, S. Nasu, T. Kawakami, and O. Shimomura, J. Phys. Soc. Jpn. 72, 2372 (2003).

Related experimental techniques

Magnetization measurement, X-ray magnetic scattering, Mossbauer spectroscopy

Questionnaire

The measurement was possible only in SPring-8. Impossible or very difficult in other facilities.
This solution is an application of a main instrument of the beamline.
With user's own instruments.

Ease of measurement

Middle

Ease of analysis

Middle

How many shifts were needed for taking whole data in the figure?

More than ten shifts