Quantum Coherent Control of Atomic and Molecular Spins on Surfaces

• Applicant: Professor Dr. Philip Willke
• Subject Area: Experimental Condensed Matter Physics
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 440339959

The quantum nature of a physical system often emerges from its fundamental building blocks and demands a profound understanding to harvest its advantages for quantum devices. Their design requires knowledge of the atomic-scale environment of a quantum object to protect it from noise and energy exchange. Scanning probe methods are able to resolve quantum systems such as single atoms and molecules on a microscopic scale, but often cannot simultaneously perform coherent manipulation of their quantum properties as common in other architectures. In this proposal, I aim to establish coherent control of single atoms and molecules on surfaces by advancing the recently realized combination of electron spin resonance and scanning tunneling microscopy. The main goal is to create a new solid-state architecture for magnetic sensing and quantum information processing operating on the atomic scale. I want to achieve this by i) improvements in instrumentation, ii) exploring new atomic-scale spin systems and iii) implementing new experimental methods such as pulsed electron and nuclear spin resonance of single atoms. For improving the instrumentation, I will integrate a scanning tunneling microscope in a table-top dilution refrigerator, a design that is unique at the host institution in the group of Wolfgang Wernsdorfer. I aim to gain a fundamental understanding of relaxation and decoherence dynamics of electron and nuclear spins of single atoms. Moreover, I plan to explore single molecular magnets as candidates for versatile nanoscale sensors in order to study magnetism in condensed matter systems. Based on the results and improvements in the preceding parts, I want to move towards quantum information processing, establishing quantum logic operations and quantum entanglement on single atomic and molecular spins.

• DFG Programme: Independent Junior Research Groups
• Major Instrumentation: Cold Head Cryogenfree ; RF generator (analog, 40GHz) ; STM system
• Instrumentation Group: 5091 Rasterkraft-Mikroskope ; 6300 Meßgeneratoren, Meßsender, Frequenznormale ; 8520 Kryostaten, Tauchkühler (bis -100 Grd C)