

- Warsaw-4-PhD School
- Doctoral studies
Gratulacje dla Marty Sawickiej! Projekt BANANO – najlepszy

Z radością zawiadamiamy, że projekt naszej koleżanki dr inż. Marty Sawickiej znalazł się na pierwszym miejscu listy rankingowej w konkursie SMALL GRANT SCHEME, ogłoszonej dziś przez Narodowe Centrum Badań i Rozwoju.
Projekt „Buried periodic Arrays of NANOchannels for single-frequency nitride lasers” będzie miał na celu wykorzystanie synergii kilku zaawansowanych technologii w celu otrzymania laserów opartych na GaN o jednomodowym widmie (ang. distributed feedback laser diodes - DFB LDs). Innowacyjność zaproponowanego podejścia polega na umieszczeniu siatki dyfrakcyjnej wewnątrz struktury. Będzie to możliwe dzięki zastosowaniu elektronolitografii, implantacji krzemem i trawienia elektrochemicznego. Schemat przyrządu prezentuje grafika poniżej (autor Mateusz Hajdel). Projekt będzie realizowany w Laboratorium Epitaksji MBE.
Streszczenie projektu:
The project addresses the unsolved question about production technology of single-frequency lasers emitting in visible range 380-530 nm, in particular distributed feedback laser diodes (DFB LDs) based on GaN. One stable wavelength operation with high side mode suppression ratio is required for such applications as: high-speed, last-mile communication based on plastic optical fibers, precise time measurements by atomic clocks or advanced sensors based on interferometry. The nitride DFB LDs are not yet available on the market because of severe limitations related to inherent material properties of (In,Al,Ga)N alloys, namely: low refractive index contrast and high lattice mismatch. A few concepts to address these issue have been reported, utilizing a photonic grating on top of LD structure. Project PI, Marta Sawicka, based on her earlier work on electrochemical etching of GaN:Si, proposes a novel approach, namely introduction of periodic arrays of nanometer size air-channels to GaN in order to locally obtain a much lower refractive index and form a photonic grating. A goal of the project is to develop a combination of two technologies: ion implantation and electrochemical etching in order to fabricate buried photonic structure (air-GaN grating) that could be located below the active region of the device. Such grating will be integrated in a blue LD structure grown by plasma-assisted molecular beam epitaxy for light coupling and dedicated wavelength selection in order to demonstrate novel design nitride DFB LD. Performance of such development will be investigated theoretically and characterized experimentally in order to verify the applicability of the proposed invention.