Robust coherent control of solid-state spin qubits using anti-Stokes excitation

Area of Science:

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

Background:

• Optically addressable solid-state color center spin qubits are crucial for quantum information processing, networks, and sensing.
• Traditional optically detected magnetic resonance (ODMR) readout relies on Stokes excitation, where laser energy exceeds emission photon energy.

Purpose of the Study:

• To investigate an unconventional anti-Stokes excitation approach for ODMR signal detection of silicon vacancy (SiV) spin defects in silicon carbide (SiC).
• To explore the potential of anti-Stokes excitation for enhanced spin qubit readout.

Main Methods:

• Systematic study of anti-Stokes excited ODMR signal dependence on laser power, microwave power, and temperature for SiV defects in SiC.
• Realization of coherent spin control under anti-Stokes excitation at room temperature.
• Development of a theoretical model to explain the enhanced spin readout contrast.

Main Results:

• Anti-Stokes excited ODMR exhibits similar behavior in contrast and linewidth to Stokes excitation.
• The ODMR contrast achieved with anti-Stokes excitation is several times greater than that of Stokes excitation.
• Spin coherence properties under anti-Stokes excitation are comparable to Stokes excitation, but with approximately three times greater signal contrast.

Conclusions:

• Anti-Stokes excitation provides a significantly enhanced spin readout contrast for SiV spin qubits in SiC.
• This method maintains comparable spin coherence properties to traditional Stokes excitation.
• The anti-Stokes excitation ODMR approach shows promising applications for improving quantum information processing and quantum sensing technologies.