Abstract
Improving the magnetic stability of single-molecule magnets is a key challenge facing molecular spintronics. We use x-ray magnetic circular dichroism to explore the possibility of magnetically stabilizing ${\mathrm{TbPc}}_{2}$ molecules by attaching them to ultrathin Fe and FeMn films. We show that ${\mathrm{TbPc}}_{2}$ deposited on antiferromagnetic FeMn films exhibits magnetic hysteresis and exchange bias as a consequence of coupling to the uncompensated interfacial Fe spins. The FeMn-thickness dependence of the coercive field and exchange bias of ${\mathrm{TbPc}}_{2}$ is similar to that of inorganic ferromagnetic/antiferromagnetic systems. The magnetic remanence is comparable with the fraction of molecules attached to pinned interfacial Fe spins. The Tb magnetic moments are antiferromagnetically coupled to the Fe thin films as well as to the uncompensated Fe spins at the FeMn interface. The sign of the coupling changes from antiferromagnetic to ferromagnetic after doping the interface with electron-donor Li atoms.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call