Magneto-transport measurement of a new Uranium-based 2D antiferromagnet

The interplay between strong correlation, magnetism, and band topology gives rise to various exciting quantum phenomena, including integer and fractional quantum anomalous Hall effects, charge density wave, unconventional superconductivity, … Recently, a new Uranium-based, van der Waals layered antiferromagnet with high Neel temperature (T_N~150K), has been successfully synthesized and emerged as a promising intrinsic material platform to study such interplay due to the possible heavy fermionic nature and strong spin orbit coupling of Uranium. In this work, we present magneto-transport and magnetic circular dichroism studies in this Uranium-based antiferromagnet from bulk single crystal down to a few atomic layer thin flakes. Noticeably, despite its antiferromagnetic ground state, we observe finite anomalous Hall signal in thin flakes, which is absent in the bulk. The magnetic hysteresis loop measured in both transport and magnetic dichroism measurements starts to appear below T_N, and its coercive field grows quickly with decreasing temperature to as high as 8T at ~90K. Our study reveals the substantial effect of dimensionality on this unique antiferromagnetic system.