Morphology and Dzyaloshinskii-Moriya interaction at thin film interfaces (Dr Thomas Moore with Prof Wen-Xin Tang @ U.Chongqing)

The interfacial Dzyaloshinskii-Moriya interaction generates a chiral twist in magnetic moments at the interface of a ferromagnet such as Co and a heavy element such as Pt with large spin-orbit coupling.  This leads to magnetic domain walls of uniform chirality, and topologically stable magnetic domains known as skyrmions.  Such chiral magnetic objects have potential applications in magnetic memory and sensor technology.  It is known from theory that different ferromagnet-large spin-orbit material combinations, e.g. Co/Pt, Fe/Ir, generate different magnitudes and signs of DMI, but in device-ready materials the interfaces are difficult to control and different measurement techniques yield different results.  Indications are that the morphology of the interface significantly affects the DMI.

This project will utilise the unique aberration-corrected low-energy electron microscope at Chongqing University to examine the morphology of ultrathin Co films grown on Pt under different conditions.  Magnetic characterisation, including measurement of DMI, will be performed at the University of Leeds.  This is a joint project between the Universities of Leeds and Chongqing.  We are looking for a motivated student with a background in condensed matter physics, materials science or similar, preferably with experience in magnetism or thin film properties.  The Condensed Matter group at the University of Leeds is one of the U.K.’s leading research groups in nanomagnetism and spintronics.  It possesses an extensive suite of facilities for materials growth, nanoscale fabrication and sample characterisation.  The Ultrafast Surface dynamics group at the Chongqing University is one of the leading groups in surface science in China. It possesses in-situ high resolution electron microscope including LEEM/PEEM/STM facilities for surfaces/interface research.