High efficiency radio frequency antennas for amplifier free quantum sensing applications

Area of Science:

• Quantum Information Science
• Materials Science
• Electrical Engineering

Background:

• Radio frequency (RF) signals are crucial for manipulating spin states in quantum applications.
• Efficiently coupling RF signals to quantum systems, such as nitrogen vacancy (NV) centers in diamond, requires specialized antennas.
• NV centers in diamond are widely used for quantum sensing via optically detected magnetic resonance (ODMR).

Purpose of the Study:

• To design and fabricate high-efficiency coplanar RF antennas for quantum sensing applications.
• To enable efficient RF signal coupling to NV defects in diamond for enhanced magnetic field sensing.

Main Methods:

• Design of single and double ring coplanar RF antennas.
• Fabrication of the designed coplanar RF antennas.
• Characterization of antenna performance using return loss measurements and magnetic field sensing experiments with NV centers.

Main Results:

• Achieved a return loss of -37 dB at 2.87 GHz, the characteristic frequency for NV defects.
• Demonstrated high antenna efficiency in magnetic field sensing experiments using NV color centers.
• Enabled ODMR experiments with standard RF signal generators (0 dB output), eliminating the need for RF amplifiers.

Conclusions:

• The developed coplanar RF antennas offer high efficiency for quantum sensing applications.
• These antennas facilitate improved RF signal coupling to NV defects in diamond.
• The high efficiency simplifies experimental setups by removing the requirement for external RF amplification.