Manipulating magnetism and transport properties of EuCd${}_2$P${}_2$ with a low carrier concentration

Abstract

Materials that exhibit strongly coupled magnetic order and electronic properties are crucial for both fundamental research and technological applications. However, finding a material that not only shows remarkable magnetoresistive responses but also has an easily tunable ground state remains a challenge. Here, we report successful manipulation of the magnetic and transport properties of EuCd${}_2$P${}_2$, which is transformed from an A-type antiferromagnet ($T_{\mathrm{N}}$ = 11 K) exhibiting colossal magnetoresistance into a ferromagnet ($T_{\mathrm{C}}$ = 47 K) with metallic behavior. The dramatic alteration results from a low hole concentration of $10^{19}$ cm${}^{-3}$ induced by changing the growth conditions. Electronic structure and total energy calculations confirm the tunability of magnetism with a small carrier concentration for EuCd${}_2$P${}_2$. It is feasible to switch between the magnetic states by using field-effect to control the carrier density, thereby changing the magneto-electronic response. The controllable magnetism and electrical transport of EuCd${}_2$P${}_2$ make it a potential candidate for spintronics.