講演情報
[24a-1BB-4]Recovery of Spin Coherence Properties in Scanning Diamond NV Probes Fabricated by Ga+ Focused Ion Beam.
〇(PC)Dwi Prananto1, Yifei Wang1, Kunitaka Hayashi1, Toshu An1 (1.JAIST)
キーワード：
Diamond NV、Spin coherence time、Scanning probe microscopy
The combination of atomic force microscopy and diamond nitrogen-vacancy (NV) center resulted in a versatile quantum sensing module with high sensitivity and high resolution1), enabled by the atomic-scale quantum spin sensor and its proximity to the sample under investigation. We have developed a simple method to fabricate diamond NV probes through laser cutting and Ga+ ion FIB milling2). In this study, we investigated a post-fabrication treatment to recover its quantum spin coherence properties. To protect against detrimental effects caused by the Ga+ ions milling, an NV-hosting diamond is coated by polyvinyl alcohol and subsequent Pt-Pd coating prior to the fabrication. UV/ozone exposure to the diamond NV probe following the fabrication improves its surface condition by oxygen-termination, stabilizing the NV centers' charge state and diminishing noise-inducing surface radicals3). The effectiveness of this post-fabrication treatment is indicated by the improvement of the NV coherence properties including 2-fold improvement of Rabi oscillation contrast, 10-fold Hahn echo T2 improvement, and 2-fold longitudinal spin relaxation T1 improvement. To demonstrate the ability of the diamond NV probe as a scanning magnetometer, we image the magnetic domain structure of a ferrimagnetic garnet (BiLu)3Fe5O12, showing the ability to resolve a few hundred-nanometer magnetic domain wall structures.
References: 1) P. Maletinsky et al., Nat. Nanotechnol. 7 [5], 320 (2012). 2) Y. Kainuma et al., J. Appl. Phys. 130 [24], 243903 (2021). 3) H. Yamano et al., Jpn. J. Appl. Phys. 56 [4S], 04CK08 (2017).
References: 1) P. Maletinsky et al., Nat. Nanotechnol. 7 [5], 320 (2012). 2) Y. Kainuma et al., J. Appl. Phys. 130 [24], 243903 (2021). 3) H. Yamano et al., Jpn. J. Appl. Phys. 56 [4S], 04CK08 (2017).