Integrated source of broadband quadrature squeezed light

Area of Science:

• Quantum optics
• Integrated photonics
• Materials science

Background:

• Generating bright, single-mode squeezed light is crucial for quantum technologies.
• Integrated photonic devices offer miniaturization and scalability for quantum applications.

Purpose of the Study:

• To propose and analyze an ultra-compact silicon nitride resonator as a source of bright single-mode quadrature squeezed light at 850 nm.
• To optimize fiber-chip coupling and assess the device's squeezing performance.

Main Methods:

• Numerical simulations were used to investigate optical properties and optimize the waveguide geometry.
• An asymmetric double layer stack waveguide with inverse vertical tapers was designed for efficient fiber-chip coupling.
• Quantum noise analysis was performed to derive the output squeezing spectrum.

Main Results:

• A simulated fiber-chip coupling loss of -0.75 dB/facet was achieved.
• The device demonstrated potential for substantial quantum noise squeezing over a bandwidth exceeding 1 GHz.
• Approximately -6 dB squeezing was predicted at 75 mW pump power in the low-loss regime.

Conclusions:

• The proposed silicon nitride resonator is a promising ultra-compact source for bright squeezed light.
• Efficient fiber-chip coupling is critical for maximizing device performance.
• The device's performance indicates feasibility for advanced quantum information processing and sensing applications.