Reversals of magnetization and exchange bias field were observed in polycrystalline perovskite TmCrO3. Interestingly, the sign reversal of exchange bias can be driven by both temperature and cooling field. The temperature dependence of exchange bias reversal takes place around 31 K and the sign reversal of exchange bias driven by cooling field occurs when the system exhibits positive exchange bias. The reversals can be elucidated based on the antiferromagnetic coupling between the canted Cr 3+ moments and Tm 3+ moments. This antiferromagnetic coupling will hinder or benefit the reversal of Cr 3+ moments or Tm 3+ moments when the system were cooled under different magnetic field.

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