Magnetic nanocrystals in nitrides: assembly and performance

Among the main aims of nowadays science we can count the development of tools for the bottom- up assembling of nanostructures with predefined properties and functionalities. Semiconductor quantum dots and nanocrystals, for instance, are expected to revolutionize the performance of various commercial devices, like flash memories, low current semiconductor lasers, and single photon emitters. Due to their applications in photonics and high power electronics, nitride semiconductors are currently reaching the technological significance of silicon (Si). Therefore, the addition of magnetism to these material systems becomes promising for a wide variety of research and application prospects. Our recent works on magnetically doped nitrides have demonstrated that by applying the appropriate growth conditions and co-doping with shallow impurities, one can fabricate on demand self-assembled ordered arrays of (Gax)Fe4-xN nanocrystals embedded in GaN with either ferromagnetic or antiferromagnetic characteristics. The key objectives of this project is to exploit the recent breakthrough progress in this field to address, through an extended protocol of epitaxial growth, conventional and advanced synchrotron- based characterization: (i) the control over the formation of self-assembled magnetic nanostructures embedded in a technologically strategic semiconductor, and (ii) the functionalities of hybrid magnetic/semiconductor systems. It is expected that the beyond-state-of-the-art work proposed here will substantially contribute to the advancement of semiconductor physics, spintronics and quantum information.

Among the main aims of nowadays science we can count the development of tools for the bottom-up assembling of nanostructures with predefined properties and functionalities. Semiconductor quantum dots and nanocrystals, for instance, are expected to revolutionize the performance of various commercial devices, like flash memories, low current semiconductor lasers, and single photon emitters. Due to their applications in photonics and high-power electronics, nitride semiconductors are currently reaching the technological significance of silicon. Therefore, the addition of magnetism to these material systems becomes promising for a wide variety of research and application prospects. The key objectives of this project were to address through the optimization of the fabrication conditions: (i) the full control over the formation of self-assembled ordered arrays of magnetic nanocrystals embedded in GaN, and (ii) the functionalities of these hybrid magnetic/semiconductor systems. Within the frame of this project, it has been possible to tune the size, shape, density and magnetic properties of the embedded nanocrystals in GaN by adjusting the fabrication conditions, making them suitable for applications in magnetic memory devices. Moreover, the chemical structure at the atomic level could be identified by employing a combination of synchrotron techniques, showing the wide potential of the employed techniques to investigate similar hybrid material systems. The results obtained in the frame of this project contribute substantially to the advancement of semiconductor physics, spintronics and quantum information.