FERMI SURFACE OF A SHAPE MEMORY ALLOY OF TINI

N. Shiotani,^a I. Matsumoto,^a H. Kawata,^a J. Katsuyama,^b M. Mizuno,^b

H. Araki,^b and Y. Shirai^b

^aPhoton Factory, KEK, Tsukuba, Ibaraki 305-0801, Japan; ^bDepartment of Materials Science and Engineering, Osaka University, Suita, Osaka 565-0871, Japan (shiotani@post.kek.jp)

The TA₂ [110] phonon anomaly observed in the pre-martensitic phase of the equiatomic intermetallic compound, TiNi, by inelastic neutron scattering has suggested nesting of the Fermi surface. So far, however, no direct observation of the Fermi surface has been reported.

We study the Fermi surface of Ti_48.9Ni_51.1 via high resolution Compton scattering. The Compton profiles are measured along 28 directions in the irreducible orientation triangle of cubic symmetry. Using Fourier-Bessel reconstruction scheme the 3-dimensional electron momentum density is obtained. The LCW-folding procedure is employed to map out the occupation number density in k-space. The results are compared with band theoretical predictions by Kakeshita et al. [1] and Zhao and Harmon [2].

References

1 Kakeshita, T., Fukuda, T., and Saburi, T. (2000) Sci. Tech. Adv. Mat. 1, 63.

2 Zhao, G. L. and Harmon, B. N. (1993) Phys. Rev. B48, 2031.