Magnetic field-effect on static spin correlation in stripe ordered phase of La_2-xBa_xCuO₄

Magnetic field-effect on spin-density-wave (SDW) order was studied for the single crystals of La_2-xBa_xCuO₄ with x 0.10 (T_c 24 K) and x 0.125 (T_c < 5 K) by neutron-scattering measurements. At zero field, incommensurate peaks from both SDW and charge-density-wave (CDW) orders were observed below 40 K (50 K) in the former (latter) sample. Applying the field of 10 T perpendicular to the CuO₂ plane, the magnetic intensity in the x 0.10 sample was enhanced with the rate of 20% of that at 0 T, while in the x 0.125 sample no obvious field-effect on SDW order was confirmed under the field up to 10 T. These results suggest that the magnetic field induces enhancement of static SDW order in the superconducting sample and does not affect the well-stabilized SDW order in the non-superconducting sample of the LBCO system at x ∼ 1/8.