Photoelectric Imaging of the Optically Inactive Charge State of Silicon-Vacancy Defects in Diamond

Area of Science:

• Quantum Information Science
• Materials Science
• Solid-State Physics

Background:

• Optically active point defects in wide-bandgap semiconductors are essential for solid-state quantum technologies like quantum registers and sensors.
• Reproducible engineering of these defects is challenging due to environmental factors and complex charge dynamics.
• Many defects are not optically accessible, limiting their study and application.

Purpose of the Study:

• To investigate the switching and control of silicon vacancy (SiV) defect charge states in diamond.
• To demonstrate a novel method for imaging optically inaccessible defect states.
• To advance the understanding of defect properties for quantum technology applications.

Main Methods:

• Utilized the photoelectric detection technique for studying SiV charge state dynamics.
• Achieved direct imaging of the dark charge state of the SiV defect.
• Developed a model for SiV charge state conversion involving proximal substitutional nitrogen defects.

Main Results:

• Successfully demonstrated switching and control of single and double charge states of the SiV defect.
• Provided the first direct imaging of the dark charge state of SiV, which is not optically or EPR-addressable.
• Established a model explaining SiV charge state conversion influenced by nearby nitrogen defects.

Conclusions:

• The photoelectric detection technique offers a powerful tool for studying optically inaccessible defect states.
• Understanding and controlling SiV charge states is critical for enhancing the performance of quantum registers and sensors.
• These findings have broad implications for the charge state control of group-IV defects in diamond for quantum applications.