Executive Summary : | Organic spin valves, where two ferromagnetic (FM) layers are separated by an organic semiconductor (OsC) layer, are the latest developments in organic spintronics due to their low spin-orbit coupling, longer spin lifetime, good thermal stability, and good mobility. Recently, a combination of different FM layers, including FeCoB, Fe, Co FeNi, have been grown on C60 and Alq3 layers, resulting in unusual and significantly different magnetic properties. However, a clear picture of how effective spin-valve could be achieved using these materials for efficient spin injection has not been experimentally realized. One fundamental problem in these structures is to prepare good quality interfaces and determine the interface structure accurately to correlate the same with magnetic and transport properties unambiguously. Most literature employs techniques with insufficient depth resolution or destructive probes, and most studies are performed ex-situ, where oxidation of the surface or nonmagnetic protective layer can significantly modify the magnetic and transport properties. In this work, the potential of the x-ray standing waves (XsW) technique will be used to study some FM-OsC materials of potential interest (FM:- Fe, FeCoB, and Fe2CoAl half-metallic alloy - OsC:- Alq3 and C60) for organic spintronics. A lab-based x-ray standing wave set-up with partial support from DsT, Delhi will be developed to study interface diffusion, magnetism, and the subtle effects of factors like temperature and structural relaxation. Depth selectivity of XsW, along with complementary techniques such as ion mass spectrometry (sIMs), in-situ MOKE, Kerr microscopy, transport, and synchrotron-based nuclear resonance scattering, will be used to follow the evolution of interfaces and gain insight into the origin of peculiar magnetic and transport properties in the proposed materials. |
Co-PI: | Dr. Mukul Gupta, UGC-DAEConsortium For scientific Research, Indore, Madhya Pradesh-452001, Dr. V. R. Reddy, UGC-DAEConsortium For scientific Research, Indore, Madhya Pradesh-452001 |