Unzueta Solozabal, Iraultza2024-11-272024-11-27production.37371https://dx.doi.org/10.26876/ikergazte.i.50https://gordailua.ueu.eus/handle/123456789/2170Positroi-deuseztapen erdibizitzaren espektroskopia (PALS) erabiliz, memoria formadun aleazio etaBi2Se3 isolatzaile topologikoa ezaugarritu da. Aleazioen kasurako, hutsuneen dentsitatea, transformaziomartensitikoaren tenperatura zein propietate magnetikoak erlazionaturik daude. Hutsune hauen kon-tzentrazioak PALS teknikaren bidez neurtzen dira. Bi2Se3 isolatzaile topologikoei dagokionez, egiturakristalinoan ager daitezkeen defektuek zein beren izaerak haien egitura elektronikoa eralda dezakete.Gure lehenengo emaitzen arabera, as-grown laginen akats natiboak honako hauek dira: dira: i) Vande Walls indarren bitartez elkarturiko geruzetan kokatzen diren selenio hutsuneak, eta ii) kargaturikotranpa ionikoak, segur aski antikokapen erako akatsak direnak.We study the microstructure of shape memory alloys and topological insulators by means of positronannihilation lifetime spectroscopy.In shape memory alloys the vacancy concentration, martensitictransformation temperature and magnetism are correlated.Samples are measured by PALS, which isthe most suitable technique for the knowledge of vacancy concentration. On the other hand, defects onthe crystal structure can influence significantly the topological properties of this materials. Our resultsindicate that the native defects in the as-grown samples of Bi2Se3 are: i) selenium vacancies between thelayers bounded by the Van der Wall forces, and ii) charged shallow traps, probably antisites.Memoria Formadun AleazioakNiMnGaIsolatzaile TopologikoakBi2Se3M¨ossbauer,PALSShape Memory AlloysNiMnGaTopological InsulatorsBi2Se3M¨ossbauerPALS.FisikaKimikaintroduction