Ultra-low-noise phase gate and squeezed state rotation in a gain-and-loss-balanced coherently prepared atomic medium

Area of Science:

• Quantum Optics
• Quantum Information Science
• Atomic Physics

Background:

• Achieving ultra-low-noise quantum phase gates and squeezed state rotations is crucial for advancing quantum technologies.
• Existing methods often face challenges with noise and fidelity in quantum operations.
• Coherently prepared atomic media offer potential for novel quantum interactions.

Purpose of the Study:

• To theoretically propose an ultra-low-noise quantum phase gate and squeezed state rotation.
• To investigate noise suppression mechanisms in coherently prepared atomic systems.
• To explore the potential for high-fidelity quantum operations and field manipulations.

Main Methods:

• Theoretical modeling of a coherently prepared atomic medium.
• Analysis of balanced loss and gain mechanisms over a range of probe field frequencies.
• Investigation of optical Kerr nonlinearity for quantum phase gate implementation.
• Simulation of squeezed state rotation using a squeezed probe field.

Main Results:

• Demonstrated balanced loss and gain in the atomic system, suppressing Raman gain noise over broad frequencies.
• Exhibited strong optical Kerr nonlinearity, enabling high-fidelity <i>π</i>-phase gate operations at the quantum level.
• Showcased the ability to rotate the squeezed state of an input nonclassical field by $90^\circ$.

Conclusions:

• Gain-and-loss-balanced coherently prepared atomic media possess unique properties for noise reduction.
• The proposed system facilitates robust quantum phase gates and precise squeezed state manipulation.
• Findings open avenues for enhanced quantum information processing and quantum metrology applications.