Spin states in carbon nanotube and graphene double quantum dots with charge detection

• Antragstellerinnen / Antragsteller: Dr. Carola Meyer; Professor Dr. Christoph Stampfer
• Fachliche Zuordnung: Experimentelle Physik der kondensierten Materie
• Förderung: Förderung von 2008 bis 2015
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 39338622

Carbon nanostructures based on graphene and carbon nanotubes (CNTs) are intrinsically low-dimensional systems with promising properties for quantum electronics. Spin scattering in both material systems is expected to be small because of their low spin-orbit coupling and the small abundance of nuclear spins. Therefore, long spin relaxation and coherence times are expected, which are essential for coherent spin-based information processing. In this project, we want to explore the fundamental properties of carbon nanostructures and the electron spin relaxation within these systems. This is an important step for the development of solid-state spin qubits and quantum electronic devices in general. The spin states will be studied in quantum dots fabricated in carbon nanotubes (part A, FZJ) and in graphene in the few-electron / few-hole regime (part B, RWTH). The states will be characterized by low-loise quantum transport measurements at varying magnetic field. Different challenges have to be addressed for both material systems. In the CNT sub-project, the focus will be on implementing high-frequency techniques for the quantitative assessment of spin relaxation times and Rabi oscillations. In the graphene sub-project we focus on the fabrication and characterization of graphene double quantum dots with integrated charge detection. The elements realized in the two parts will allow measurements of spin coherence times in both material systems.

• DFG-Verfahren: Forschungsgruppen
• Teilprojekt zu: FOR 912: Coherence and relaxation properties of electron spins
• Großgeräte: Waveform Generator
• Gerätegruppe: 2610 Generatoren und rotierende Umformer