Bright squeezed-vacuum source with 1.1 spatial mode.

Area of Science:

• Quantum optics
• Nonlinear optics
• Laser physics

Background:

• Macroscopic nonclassical states of light are crucial for quantum information processing.
• Optical parametric amplifiers (OPAs) are key sources for generating such states.
• Achieving bright and spatially single-mode squeezed vacuum is a significant challenge.

Purpose of the Study:

• To generate bright squeezed vacuum with spatial single-mode properties.
• To investigate the use of a two-crystal traveling-wave optical parametric amplifier (OPA) for this purpose.
• To maintain high brightness and squeezing levels in the generated light.

Main Methods:

• Utilizing a strongly pumped, nonseeded traveling-wave optical parametric amplifier (OPA).
• Employing two consecutive crystals separated by a large distance within the OPA.
• Characterizing the spatial mode properties, brightness, and squeezing of the output light.

Main Results:

• Successfully generated bright squeezed vacuum at the output of the OPA.
• Demonstrated that the two-crystal configuration with large separation yields spatially single-mode squeezed vacuum.
• Observed no significant decrease in brightness or squeezing levels.

Conclusions:

• A two-crystal OPA configuration is effective for producing bright, spatially single-mode squeezed vacuum.
• This method offers a practical approach for generating high-quality nonclassical light.
• The findings advance the development of sources for quantum technologies.