Polaron formation in Bi-deficient BaBiO 3

W. Román Román Acevedo (1) , S Di Napoli (1, 2) , F. Romano (2) , G Rodríguez Ruiz (2, 1) , P. Nukala (3, 4) , C. Quinteros (5) , J. Lecourt (5) , Ulrike Luders (5) , V. Vildosola (2, 1) , D. Rubi (2, 1)

1 UBA - Universidad de Buenos Aires [Buenos Aires]
2 Departamento de Física [Universidad de Buenos Aires]
3 IISc Bangalore - Indian Institute of Science [Bangalore]
4 University of Groningen [Groningen]
5 CRISMAT - Laboratoire de cristallographie et sciences des matériaux

BaBiO3 is a charged ordered Peierls-like perovskite well known for its superconducting properties upon K or Pb doping. We present a study on the transport and electronic properties of BaBiO3 perovskite with strong Bi-deficiency. We show that it is possible to synthesize BaBiO3 thin layers with Bi-vacancies above 8-10% by depositing an yttrium-stabilized zirconia capping layer. By combining transport measurements with ab initio calculations we propose an scenario where the Bi-vacancies give rise to the formation of polarons and suggest that the electrical transport is dominated by the migration of these polarons trapped at Bi 3+ sites. Our work shows that cation vacancies engineering-hardly explored to date-appears as a promising pathway to tune the electronic and functional properties of perovskites.

Mots clés: Defects; Density of states; Electrical conductivity; Electronic structure; Growth; Polarons; Surface & interfacial phenomena; Vacancies; Density functional calculations

Domaines: Matériaux; Science des matériaux [cond-mat.mtrl-sci]

W. Román Román Acevedo, S Di Napoli, F. Romano, G Rodríguez Ruiz, P. Nukala, et al.. Polaron formation in Bi-deficient BaBiO 3. Physical Review B, 2021, 104 (12), pp.125307. ⟨10.1103/PhysRevB.104.125307⟩. ⟨hal-03433504⟩