Giant magnetoresistance in Y_0.9La_0.1Mn₆Sn₆ compound

Magnetic transitions and magnetoresistance effect of the HfFe_6Ge_6-type Y_0.9La_0.1Mn_6Sn_6 compound have been investigated in the temperature range of 5－380K. The sample displays antiferromagnetic behaviour in the whole temperature range below Néel temperature T_\rm N=309K. The metamagnetic transition from antiferromagnetism to ferromagnetism can be induced by an applied field. The metamagnetic transition field decreases monotonically from 2T at 5K to 0.4T at 300K. The giant magnetoresistance effect is observed with the metamagnetic behaviour, such as -10.4% at 245K under a field of 5T.