Theoretical analysis of an electrometer based on microwave-dressed Rydberg atoms using a quantum interferometer

Area of Science:

• Quantum Optics
• Atomic Physics
• Metrology

Background:

• Rydberg atoms excel at precise microwave (MW) field sensing.
• Previous Rydberg atom-based electrometers (RAEs) primarily used absorption measurements.
• Phase-sensitive RAEs exist but are limited by the standard quantum limit (SQL).

Purpose of the Study:

• To enhance MW field sensing capabilities by combining RAEs with advanced quantum interferometrics.
• To overcome the limitations of existing RAEs, particularly the SQL.
• To achieve noise suppression below the photon shot noise (PSN).

Main Methods:

• Utilizing electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting.
• Employing phase-squeezed states within a balanced SU(1,1) interferometer.
• Measuring light dispersion through microwave-dressed atoms.

Main Results:

• Demonstrated noise suppression below the photon shot noise (PSN).
• Achieved optimal MW field sensitivity of 1.36 × 10^-11 V/m/Hz^1/2.
• Required a dressed MW field strength of 2.4 × 10^-4 V/m.

Conclusions:

• The combined approach of RAEs and quantum interferometrics significantly enhances MW field sensing.
• Noise suppression below PSN is achievable, surpassing SQL limitations.
• The developed theoretical framework predicts high sensitivity for MW field measurements.