Optical absorption spectroscopy study of the role of plasma chemistry in YBa2Cu3O7 pulsed laser deposition

Time-resolved optical absorption spectroscopy techniques were used to study Ba, metastable Ba+, and YO absorptions in the laser-produced plasma plume from a YBa2Cu3O7 target. Results obtained indicate an initial explosive removal of material from the target surface followed by a subsequent evaporation process. Some YO is ejected from the target in molecular form, particularly at laser fluence <6 J/cm2, whilst additional YO is formed in subsequent reactions of Y with oxygen at the plasma plume edges. The formation of metastable Ba+ (52D5/2) is also observed in the outer reactive layers of the plasma plume.