Citation: Schätzle, Philip, et al. “Enhancing NV concentration in delta-doped diamond via low-pressure high-temperature annealing.” Diamond and Related Materials (2026): 113337.
Authors: Philip Schätzle; Sven Mägdefessel; Leon Büttner; Patrik Straňák; Aurelién Commans; Lutz Kirste; Rebekka Eberle; Volker Cimalla; Peter Knittel
Publication location: Diamond & Related Materials (Elsevier, ScienceDirect)
Date: 16 January 2026
DOI: https://doi.org/10.1016/j.diamond.2026.113337
Abstract:
We present the increase in the nitrogen vacancy center concentration in nitrogen delta-doped layers by almost one order of magnitude. To achieve this, we employ a low-pressure, high-temperature annealing step at 1750 °C in vacuum. We demonstrate an enhancement of the photoluminescence intensity of NV centers compared to annealing steps at lower temperatures of 1200 °C. To achieve this, we fabricate nitrogen-doped thin films with a thickness of 50 nm via chemical vapor deposition. We show that the nitrogen is mainly incorporated in a 6 nm thin film at the layer interface. We link the strong enhancement of the NV concentration to a possible decomposition of NVH centers and the mobility of various species at elevated temperatures, including vacancies and nitrogen in these two-dimensional structures. Additionally, after the high temperature annealing, we observe a Hahn-echo spin coherence time of 7.9 µs, which is in line with literature data on achievable coherence time in highly nitrogen-doped layers. Our results could pave the way for the precise fabrication of improved diamond elements, e.g., used in magnetic field sensors and offer an alternative route to implantation techniques.Schätzle, Philip, et al. “Enhancing NV concentration in delta-doped diamond via low-pressure high-temperature annealing.” Diamond and Related Materials (2026): 11333 .
