The detection of magnetic fields with increased spatial resolution to micro-nanoscales is very important for magnetometry. Low-dimension sensors with increased sensitivity and extended capabilities are of great interest. It was shown that graphene exhibits large magnetoresistance (MR) up to very high magnetic fields (B=62 T). However, at low fields it is small due to classical quadratic MR(B) dependence. On the other hand, lanthanum perovskite films exhibit colossal MR at low and intermediate fields, however, it saturates in high fields. The main idea of this project: using two effects of nanomaterials – large positive MR of graphene and colossal negative MR of perovskite – to develop novel compact hybrid graphene-perovskite sensor with decreased dimensions and higher sensitivity in comparison with individual graphene or perovskite sensors, and extended capability to measure magnitude of magnetic field and its direction with respect to sensor’s reference plane. The main objective is to grow graphene and lanthanum perovskite La1-xSrx (Mn1-yCoy )zO3 (LSMCO) films on the same substrate by using special chemical vapor deposition technologies MW PECVD and PI MOCVD and to fabricate hybrid graphene-perovskite structure as the main element of magnetoresistive sensor with tunable sensitivity in a wide range of magnetic fields and capability to measure magnitude of magnetic field and its direction with respect to the sensor’s reference plane. Such novel hybrid sensor would provide possibilities to decrease its dimensions for measuring magnetic fields in small volumes, especially for measurement of field direction in respect to reference plane, when in conventional methods three sensors are used. The use of industrially available technologies will result in acceleration of industrial applications of sensors based on graphene and lanthanum perovskite films.
Project funding:
Projects funded by the Research Council of Lithuania (RCL), Projects carried out by researchers’ teams
Project results:
Pulsed injection MOCVD technology will be optimized to grow nanostructured lantanum perovskite LSMCO films with determined in advance chemical composition (with excess of z=Mn+Co) and MR properties. Microwave plasma enhanced chemical vapor deposition (MW PECVD) technology will be optimized for the synthesis of graphene onto the same substrate as lanthanum perovskite film. MR properties of graphene and LSMCO films will be investigated in low (<0.5 T) and high (up to 20 T) magnetic fields. The hybrid graphene-lanthanum perovskite structure fabricated onto single substrate will be created and a prototype of hybrid magnetic field sensor, exhibiting higher sensitivity and extended capabilities in comparison with individual graphene and manganite sensors, will be developed.
Period of project implementation: 2022-05-01 - 2024-12-31
Project coordinator: Valstybinis mokslinių tyrimų institutas Fizinių ir technologijos mokslų centras
Project partners: Kaunas University of Technology
