Low-temperature magnetisation process in the cubic pyrochlore quantum antiferromagnet, Er_2Ti_2O_7

摘要

We report low-temperature susceptibility and magnetisation data for the cubic pyrochlore Er_2Ti_2O_7. By performing the measurements on single crystals we are able to establish the degree of magnetic anisotropy present in this compound and to determine the critical values for magnetic field induced transitions below the magnetic ordering temperature of 1.2 K. We also present a magnetic H-T phase diagram of this quantum XY antiferromagnet for different directions of an applied field.