Investigation of Photo-luminescence of NV rich Diamonds for Understanding Interaction with paramagnetic Centers and for quantum based sensor applications

• Applicant: Dr. Ralf Wunderlich
• Subject Area: Experimental Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 469915055

The project investigates the photoluminescence (PL) of nitrogen vacancy (NV)-rich diamonds under the influence of an external magnetic field. Coupling of a NV center with other paramagnetic defects causes the PL of the NV center to collapse under certainmagnetic fields, allowing the detection and investigation of such couplings. Such interactions affect the applicability of NV centers as quantum sensors as well as quantum information processing by NV centers. In the investigations, special attention will be paid to the interaction of NV centers with neighboring paramagnetic centers,such as substitutional nitrogen (P1), other NV centers or other interfering sites. Red, i.e. NV-rich, diamonds offer an excellent opportunity to study such couplings in an ensemble with a high signalto-noise ratio (SNR). For the generation of such samples nitrogen-richhigh pressure high temperature produced diamonds are used, which are irradiated with high energy electrons. This creates vacancies which lead to the formation of NV centers by simultaneous heating. The temperature can be controlled by the beam current and thedensity of the vacancies can be varied by the accumulated fluence of the irradiation. In combination of magnetic field and angle dependent PL measurements, electron paramagnetic resonance (EPR), particle induced X-ray emission (PIXE), and numerical simulations, the typical PL of NV-rich/red diamonds shall be understood.

• DFG Programme: Research Grants