Details

Autor(en) / Beteiligte

• Rosskopf, T
• Dussaux, A
• Ohashi, K
• Loretz, M
• Schirhagl, R
• Watanabe, H
• Shikata, S
• Itoh, K M
• Degen, C L

Titel

Investigation of surface magnetic noise by shallow spins in diamond

Ist Teil von

• Physical review letters, 2014-04, Vol.112 (14), p.147602-147602, Article 147602

Ort / Verlag

United States

Erscheinungsjahr

2014

Quelle

American Physical Society Journals

Beschreibungen/Notizen

• We present measurements of spin relaxation times (T1, T1ρ, T2) on very shallow (≲5  nm) nitrogen-vacancy centers in high-purity diamond single crystals. We find a reduction of spin relaxation times up to 30 times compared to bulk values, indicating the presence of ubiquitous magnetic impurities associated with the surface. Our measurements yield a density of 0.01-0.1μB/nm2 and a characteristic correlation time of 0.28(3) ns of surface states, with little variation between samples and chemical surface terminations. A low temperature measurement further confirms that fluctuations are thermally activated. The data support the atomistic picture where impurities are associated with the top carbon layers, and not with terminating surface atoms or adsorbate molecules. The low spin density implies that the presence of a single surface impurity is sufficient to cause spin relaxation of a shallow nitrogen-vacancy center.