Development of a high quality thin diamond membrane with embedded   nitrogen-vacancy centers for hybrid spin-mechanical quantum systems
  Hybrid quantum systems (HQSs) have attracted several research interests in the last years. In this Letter, we report on the design, fabrication, and characterization of a novel diamond architecture for HQSs that consists of a high quality thin circular diamond membrane with embedded near-surface nitrogen-vacancy centers (NVCs). To demonstrate this architecture, we employed the NVCs by means of their optical and spin interfaces as nanosensors of the motion of the membrane under static pressure and in-resonance vibration, as well as the residual stress of the membrane. Driving the membrane at its fundamental resonance mode, we observed coupling of this vibrational mode to the spin of the NVCs by Hahn echo signal. Our realization of this architecture will enable futuristic HQS-based applications in diamond piezometry and vibrometry, as well as spin-mechanical and mechanically mediated spin-spin coupling in quantum information science. 
S. Ali Momenzadeh, Felipe F\'avaro de Oliveira, Philipp Neumann, D. D.   Bhaktavatsala Rao, Andrej Denisenko, Morteza Amjadi...
cond-mat.mes-hall