Uniform Doping in Quantum-Dots-Based Dilute Magnetic Semiconductor.
Effective manipulation of magnetic spin within a semiconductor leading to a search for ferromagnets with semiconducting properties has evolved into an important field of dilute magnetic semiconductors (DMS). Although a lot of research is focused on understanding the still controversial origin of magnetism, efforts are also underway to develop new materials with higher magnetic temperatures for spintronics applications. However, so far, efforts toward quantum-dots(QDs)-based DMS materials are plagued with problems of phase separation, leading to nonuniform distribution of dopant ions. In this work, we have developed a strategy to synthesize highly crystalline, single-domain DMS system starting from a small magnetic core and allowing it to diffuse uniformly inside a thick CdS semiconductor matrix and achieve DMS QDs. X-ray absorption fine structure (XAFS) spectroscopy and energy-dispersive X-ray spectroscopy-scanning transmission electron microscopy (STEM-EDX) indicates the homogeneous distribution of magnetic impurities inside the semiconductor QDs leading to superior magnetic property. Further, the versatility of this technique was demonstrated by obtaining ultra large particles (∼60 nm) with uniform doping concentration as well as demonstrating the high quality magnetic response.
Avijit
A
Saha
Amitha
A
Shetty
A R
AR
Pavan
Sector 10 ID, CSRRI-IIT, Advanced Photon Source, 9700 South Cass Avenue, Lemont, Illinois 60439, United States.|Advanced Materials Group, Physics Department, Illinois Institute of Technology , Chicago, Illinois 60616, United States.
Soma
S
Chattopadhyay
MRCAT, Argonne National Laboratory , Argonne, Illinois 60439, United States.|Advanced Materials Group, Physics Department, Illinois Institute of Technology , Chicago, Illinois 60616, United States.
Tomohiro
T
Shibata
Ranjani
R
Viswanatha