Speaker
Description
Spin and charge correlations are particularly pronounced in nanoscale materials and enable new technologies that harness quantum behavior. Accessing these correlations on their intrinsic length and time scales is an important step towards a microscopic understanding of correlated-electron physics.
We combine scanning tunneling microscopy with pump probe schemes [1] to achieve ultrafast spectroscopy of spin and charge dynamics with atomic spatial resolution. Using different electronic and optical techniques it is possible to achieve time resolution between milliseconds and femtoseconds thereby matching the instrument to the dynamics of the investigated system. In this talk I will review recent advances in ultrafast scanning probe microscopy and then discuss two experiments: one in which we fabricated a few-atom spin sensor that dynamically measures minute magnetic interactions with nearby magnetic atoms [2]; and one in which we observe the ultrafast motion of a two-dimensional correlated-electron state in the vicinity of defects.
These experiments shed light onto the impact of correlations and coherences in quantum materials and highlight pathways to design and control matter at the single atom level.
References
[1] S. Loth, M. Etzkorn, C. P. Lutz, D. M. Eigler, A. J. Heinrich, Science 329, 1628 (2010).
[2] S. Yan, L. Malavolti, J. Burgess, S. Loth, Science Adv. 3 e1603137 (2017).
