resumo
In muon-spin-rotation experiments, positive muons are implanted in the material and come to rest in the unrelaxed host lattice. The formation of the final configuration requires a lattice relaxation which does not occur instantly. The present paper is concerned with the transition from the initial stopping state to the final muon configuration. We identify the often observed fast relaxing signal in muon experiments (e.g., in several oxides studied recently) with the transition state in this conversion process. This state is paramagnetic with a small hyperfine interaction (in the order of MHz) which fluctuates and averages to almost zero. Because of its apparent diamagnetic frequency behavior, the fast signal was in the past assigned to Mu(+) or Mu(-). We present evidence that this state is actually paramagnetic. The model presented in this paper is of importance for the interpretation of past and future mu SR measurements.
palavras-chave
VI-SEMICONDUCTOR COMPOUNDS; SAPPHIRE; HYDROGEN; DYNAMICS; GAP
categoria
7
autores
Vilao, RC; Vieira, RBL; Alberto, HV; Gil, JM; Weidinger, A
nossos autores
agradecimentos
ApostolosMarinopoulos is thanked for helpful discussions. This work was supported with funds from (i) FEDER (Programa Operacional Factores de Competitividade COMPETE) and from FCT - Fundacao para a Ciencia e Tecnologia under projects UID/FIS/04564/2016 and PTDC/FIS/102722/2008; (ii) PhD Grant No. SFRH/BD/87343/2012 from FCT Fundacao para a Ciencia e Tecnologia (RBLV).