Weak Electron Irradiation Suppresses the Anomalous Magnetization of N‐Doped Diamond Crystals

• Published in: physica status solidi (b) 2021-11, Vol.258 (11), p.n/a
• Main Authors: Setzer, Annette, Esquinazi, Pablo D., Daikos, Olesya, Scherzer, Tom, Pöppl, Andreas, Staacke, Robert, Lühmann, Tobias, Pezzagna, Sebastien, Knolle, Wolfgang, Buga, Sergei, Abel, Bernd, Meijer, Jan
• Format: Article
• Language: English
• Subjects: color centers; diamond; magnetism
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/pssb.202100395

Several diamond bulk crystals with a concentration of electrically neutral single substitutional nitrogen atoms of ≲80 ppm, the so‐called C or P1 centers, are irradiated with electrons at 10 MeV energy and low fluence. The results show a complete suppression of the irreversible behavior in field and temperature of the magnetization below 30 K, after a decrease in ≲40 ppm in the concentration of C centers produced by the electron irradiation. This result indicates that magnetic C centers are at the origin of the large hysteretic behavior found recently in nitrogen‐doped diamond crystals. This is remarkable because of the relatively low density of C centers, stressing the extraordinary role of the C centers in triggering those phenomena in diamond at relatively high temperatures. After annealing the samples at high temperatures in vacuum, the hysteretic behavior is partially recovered. The irreversible field‐ and temperature‐dependent behavior of the magnetization of nitrogen‐doped diamond bulk crystals below ∼30 K, is completely suppressed after irradiation with electrons at ∼10 MeV energy and low fluence. This effect is related to the decrease in the concentration of magnetic C centers after electron irradiation, stressing their extraordinary role in triggering irreversible phenomena at relatively high temperatures.