B02 Photon driven energy transfer across correlated interfaces (Jooss, Seibt)

The main goal of this project is to study fundamental mechanisms energy conversion at interfaces between perovskite oxides with tunable correlations. Active control of energy conversion through quasiparticle lifetimes and diffusion lengths will be achieved by inducing charge order-disorder transitions which will be studied at high spatial and temporal resolution. We want to study whether the formation of “hot polaron-type” excited states from a pathway for efficient conversion of photons into chemical and finally into electrical energy.

Fig. 1: Photovoltaic analysis of manganite/titanate heterostructures:
a) sample geometry and measurement setup for photovoltaic basic characterization,
b) IV-curves with and without illumination for two temperatures

Fig. 2: High resolution microscopy necessary for controlled design of interfaces:
a) HRSTEM image of the pn-interface of a manganite/titanate heterostructure: Nearly defect free and atomically sharp interface.
b) Scheme of orbital matching of the interface.

Fig. 3: Development of new measurement setup for microscopic analysis of pn-heterostructures e.g. electron beam induced current (EBIC) measurement in a TEM for determination of small diffusion length and local probing of the PV effect.