X‐Rays in Diamond Photonics: A New Way to Control Charge States of Color Centers

This work is focused on the investigation of the X‐ray's interaction with the color centers in diamond. X‐rays have the high penetrating power of radiation, which allows performing unhindered modifications deeply in the bulk of diamond crystals. Herein, it is shown that X‐rays irradiation of diamond can change the charge states of its defects, including silicon‐vacancy (SiV) and nitrogen‐vacancy (NV) color centers. By studying low‐temperature absorption spectra, it is shown that negatively charged SiV− and NV− centers partially transform into neutrally charged SiV0 and NV0 centers, accordingly. In addition, new absorption lines are registered, which may belong to other charge states of color centers. The results open a new way for the study of charge states for defects in various crystals (not limited to diamond), as well as allow the control over the charge state of color centers for diamond‐based quantum optics. Herein, it is shown that X‐rays in diamond can change the charge states of color centers, for which silicon‐vacancy (SiV) and nitrogen‐vacancy (NV) have been used. X‐rays have been shown to change the charge states of color centers toward more positive ones. Unlike UV radiation, X‐rays have a greater penetrating power and affect the entire volume of the diamond.