International Exchange Award: Correlating cryo-MOKE imaging and transport in 2D chiral helimagnet devices
Posted on 24th April 2026 in News
During the visit, Guzmán Orero Gámez (left), PhD student at UAM, and Chenghao Yang (UCL) worked on the cryo-MOKE setup, mounting the sample and adjusting the magnetic poles for low-temperature MOKE and transport measurements.Chenghao Yang, a PhD student from University College London (UCL) was awarded an M4QN international exchange award to visit Prof. Saül Vélez at the Spintronics and Nanodevices Lab, IFIMAC, Universidad Autónoma de Madrid (UAM). The visit took place from 23-31 March 2026.
Correlating cryo-MOKE imaging and transport in 2D chiral helimagnet devices
The visit enabled a focused UCL–UAM exchange on low-temperature magneto-optical Kerr effect (cryo-MOKE) measurements for exfoliated 2D chiral helimagnet devices. The main goal was to establish a practical workflow for correlating magnetic imaging with electrical transport and current-pulse control in Cr1/3NbS2-based devices.
During the visit, they worked on optical alignment, Kerr-contrast optimisation, field and temperature measurement protocols, and benchmarking the sensitivity of the setup on relevant samples. This allowed those involved to assess how best to image field-driven magnetic evolution in their devices and to compare those observations directly with transport signatures such as low-field magnetoresistance and switching behaviour. The visit also provided hands-on training in the use of the cryo-MOKE system and helped define the experimental conditions, sample requirements and analysis steps needed for reliable future measurements.
Benefits to the UK materials and quantum community
This visit benefits the UK materials and quantum community by transferring a specialised experimental capability into an active UK research programme and by strengthening links between UK researchers and a leading European spintronics laboratory. For UK groups working on 2D magnets, spin textures and quantum-device-relevant materials, one of the major challenges is connecting electrical signals to the underlying magnetic configuration. The cryo-MOKE workflow developed through this visit helps address that gap by enabling direct comparison between magnetic imaging, transport and current-driven switching in the same class of devices.
The work fits strongly with M4QN’s goals as it brings together materials research and quantum-device motivation, supports the formation of new interdisciplinary collaborations, and contributes to the development of practical skills in advanced characterisation of quantum materials. It is particularly relevant to the network’s 2D Materials and Spin and Topology communities, while also aligning with its broader themes of international engagement and training. By building a reusable measurement and analysis approach rather than a one-off dataset, the visit also creates something that can be shared more widely across the network.
In the longer term, this exchange helps position the UK community to study low-power spin-based device concepts with stronger microscopic understanding, which is important for future sensing, information storage and quantum-enabled technologies.
Visit Outcomes
Chenghao writes “The visit led to several important outcomes. It established a stronger and more structured collaboration between UCL and UAM on cryogenic MOKE studies of 2D magnetic and spintronic devices, and provided a shared experimental workflow for correlating magnetic imaging with electrical transport and current-pulse measurements. The discussions and benchmark measurements carried out during the visit also helped identify practical directions for improving both device structure and experimental design, including sample selection, geometry optimisation, thickness control, contact layout and measurement conditions for more reliable magnetic and transport correlation. These outcomes have provided a clearer strategy for the next stage of experiments on Cr1/3NbS2-based devices and related systems, and have strengthened the basis for a potential joint publication once a fuller dataset is completed. More broadly, the visit created a foundation for future reciprocal visits, follow-on collaborative experiments, and possible joint funding applications, while also contributing new methodological knowledge that can benefit wider work on spin, topology and 2D quantum materials.”