Quantum sensing of emergent phenomena in materials

ABSTRACT: 

Interactions between particles in a many-body quantum system can lead to emergent collective phenomena. This is particularly evident in the solid state, where electrons in a solid can exhibit a wide variety of collective properties, from magnetism to superconductivity, depending on the structure and chemistry of their host material. The newest frontier in this landscape involves emergent phenomena in materials — quantum liquids, spin-charge separation, and quantum criticality in metals, among others — that challenge our existing frameworks of many-body quantum physics. Experimentally testing the evolving theories in this frontier requires advancements in both the design of the host materials, and the development of new techniques to probe their emergent physics. I will describe how synthetic techniques can be used to tune the interactions, symmetries, and dimensionality governing the electrons in a material to realize desired emergent phenomena, and how quantum sensors can be leveraged as a unique nanoscale probe of these systems. In particular, I will describe an example in which we use the coherence properties of color centers in diamond to detect signatures of a hydrodynamic spin mode in an atomically-thin magnetic insulator. The integration of materials synthesis and quantum sensing techniques has the potential to not only shed new light on existing problems like high-temperature superconductivity, but also to raise new questions about how many-body quantum systems can be used to store, process, and transmit the quantum information generated by the sensor.

BIO:

Nikola is currently an ORISE postdoctoral fellow at Harvard University. His current research focuses on using quantum sensing microscopy to study the emergent properties of low-dimensional magnets and superconductors. Before moving to Harvard, Nikola completed his physics PhD at University of California Berkeley under the supervision of Prof. James Analytis. His dissertation focused on synthesis and bulk characterization of strongly correlated materials, including rare-earth metals, iron-based superconductors, and metallic Van der Waals magnets.