|Budget Amount *help
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2002: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2001: ¥2,300,000 (Direct Cost: ¥2,300,000)
From pulsed-neutron diffraction measurements of single crystal DyRu_2Si_2, we have confirmed that at the high temperature phase the magnetic modulation is one-dimensional with Q=(2/9 0 0). On the other hand, at the intermediate temperature phase many magnetic satellites on low-symmetry lines as well as high-symmetry lines have been observed in the a^*-b^* reciprocal plane. This is the evidence for the modulation being not one-dimensional but two-dimensional. The distribution of the magnetic satellites is reproduced by a magnetic unit cell of 9a×9a×c, in which the corner and the body-centered Dy ions are effectively paramagnetic due to frustration. Furthermore, pulsed-neutron experiments under magnetic fields at the ISIS, we have made clear the magnetic modulation of the four metamagnetic phases at low temperatures .
From single crystal neutron diffraction studies of TbRu_2Si_2 at Risoe National Laboratory, Denmark we have confirmed that the magnetic modulation is one-dimensional with Q=(3/13 0 0), but established the modulation for the intermediate temperature phase (ITP) to be two-dimensional of the magnetic unit cell being 13a×13a×c, including two frustrated Tb ions at the corner and body-centered positions, similar to the modulation of DyRu_2Si_2. Furthermore, for the low temperature phase two domains of a domain with Q=(3/13 1/4 0) and the ITP domain slightly distorted monoclinically in the a-b plane coexist.