Speaker
Dr
Alexander V. Boris
(Max-Planck-Institut fuer Festkoerperforschung, Stuttgart, Germany)
Description
Recent advances in the synthesis of transition metal oxides (TMO) heterostructures with atomically sharp interfaces open new functionalities by tuning the interfacial properties of correlated electron materials, in the same manner as for semiconductor heterostructures. Motivated by the desire to realize the potential of TMO heterostructures in controlling collective quantum phases, we have built devices out of atomically thin layers of two different TMOs - LaNiO3 and LaAlO3 - which are metallic and insulating in bulk form, respectively. To explore the behavior of electrons in the atomically thin layers, we have used a suite of advanced experimental probes such as synchrotron-based infrared ellipsometry and low-energy muon spin rotation (at the LEM beamline of the PSI). When the layers are more than three atomic monolayers thick, the electrons were found to behave in a manner closely similar to the one in the bulk. In heterostructures where the conduction electrons are confined to two atomic monolayers separated by insulating layers, their behavior changes completely, exhibiting a sequence of two collective phase transitions upon cooling. We have provided strong evidence that these transitions correspond to the onset of charge and antiferromagnetic spin order. We have thus demonstrated that the collective electronic phases in these TMO devices can be accurately controlled by adding a single atomic monolayer.
Please specify the session
Plenary session
Please specify poster or talk
Talk
Primary author
Dr
Alexander V. Boris
(Max-Planck-Institut fuer Festkoerperforschung, Stuttgart, Germany)
