Recently antiferromagnets have been identified as promising building blocks of novel data storage devices since they are robust against stray fields due to the absence of net magnetization, their domains can be on the nanoscale and reproducibly switched unlimited times, moreover, their spin dynamics is orders-of-magnitudes faster compared to ferromagnets. However, the detection and manipulation of antiferromagnetic (AFM) domains that is crucial for the development of antiferromagnetic spintronics are highly challenging as usual methods utilized in ferromagnets does not work. A possible way-out is the application of non-centrosymmetric antiferromagnets where the so-called magnetoelectric (ME) effect is allowed. In these materials the simultaneous absence of spatial inversion and time-reversal symmetries allows couplings between the electric field and the magnetization as well as between the magnetic field and the electric polarization, resulting in the magnetoelectric (ME) response.
Our group has found that the ME effect is active at finite frequencies as well and gives rise to novel optical effects that results in light absorption difference for the AFM domains. Recently, we demonstrated such optical read-out of the ME domains in THz frequency range. In the course of this experimental PhD project the applicant will study the ME domains of non-centrosymmetric antiferromagnets by GHz-THz and optical spectroscopy. (S)he will develop microwave and optical probes to detect AFM domains by the radiation and at the same time to control their state by the application of static electric and magnetic fields. Eventually, the domain control by electromagnetic fields via highly non-linear interactions between light and matter will be investigated.
Good knowledge of solid state physics, motivation for experimental work in condensed matter physics.