摘要 :
We use neutron scattering to study the Pr~(3+) crystalline electric field (CEF) excitations in the filled skutteru-dite PrOs_4As_(12). By comparing the observed levels and their strengths under neutron excitation with the theoreti...
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We use neutron scattering to study the Pr~(3+) crystalline electric field (CEF) excitations in the filled skutteru-dite PrOs_4As_(12). By comparing the observed levels and their strengths under neutron excitation with the theoretical spectruniand neutron
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摘要 :
We report neutron-scattering studies of the spin correlations of the geometrically frustrated pyrochlore Tb_2Mo_2O_7 using single-crystal samples. This material undergoes a spin-freezing transition below T_g approx= 24 K, similar ...
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We report neutron-scattering studies of the spin correlations of the geometrically frustrated pyrochlore Tb_2Mo_2O_7 using single-crystal samples. This material undergoes a spin-freezing transition below T_g approx= 24 K, similar to Y_2Mo_2O_7, and has little apparent chemical disorder. Diffuse elastic peaks are observed at low temperatures, indicating short-range ordering of the Tb moments in an arrangement where the Tb moments are slightly rotated from the preferred directions of the spin-ice structure. In addition, a Q~→-independent signal is observed which likely originates from frozen but completely uncorrelated Tb moments. Inelastic measurements show the absence of sharp peaks due to crystal-field excitations. These data show how the physics of the Tb sublattice responds to the glassy behavior of the Mo sublattice with the associated effects of lattice disorder.
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摘要 :
We report on neutron-scattering results on the impact of a magnetic field on stripe order in the cuprate La_(1.875)Ba_(0.125)CuO_4. It is found that a 7 T magnetic field applied along the c axis causes a small but finite enhanceme...
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We report on neutron-scattering results on the impact of a magnetic field on stripe order in the cuprate La_(1.875)Ba_(0.125)CuO_4. It is found that a 7 T magnetic field applied along the c axis causes a small but finite enhancement of the spin-order peak intensity and has no observable effect on the peak width. Inelastic neutron-scattering measurements indicate that the low-energy magnetic excitations are not affected by the field, within experimental error. In particular, the small energy gap that was recently reported is still present at low temperature in the applied field. In addition, we find that the spin-correlation length along the antiferromagnetic stripes is greater than that perpendicular to them.
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