Highly sensitive Rydberg atom-based terahertz heterodyne receiver enabled by array-beam excitation.

Area of Science:

• Atomic physics
• Metrology
• Terahertz (THz) technology

Background:

• Rydberg atom-based terahertz (THz) metrology offers high precision.
• Current electric-field sensitivity limits practical applications compared to other THz receivers.

Purpose of the Study:

• To enhance the electric-field sensitivity of a Rydberg atom-based THz heterodyne receiver.
• To explore the potential of multi-beam laser arrays for improving THz detection.

Main Methods:

• Utilized a 3x3 laser-beam array in a Rydberg atom-based THz heterodyne receiver setup.
• Operated the receiver at a terahertz frequency of 0.3 THz.
• Measured electric-field sensitivity and minimum-detectable power.

Main Results:

• Achieved a 7.6 dB improvement in sensitivity compared to a single-beam configuration.
• Reached an electric-field sensitivity of 35.8±1.4 nV cm⁻¹ Hz⁻¹/².
• Obtained a minimum-detectable power of -149 dBm at a 1-Hz bandwidth.

Conclusions:

• The multi-beam laser array significantly enhances Rydberg atom-based THz receiver sensitivity.
• The achieved sensitivity approaches that of an ideal λ/2 metallic antenna.
• This advancement paves the way for practical THz radar and communication applications.