On-demand continuous-variable quantum entanglement source for integrated circuits

Area of Science:

• Quantum optics
• Nanophotonics
• Integrated quantum circuits

Background:

• Integrating devices that generate non-classical states, like entanglement, into photonic circuits is key for advanced quantum technologies.
• Controlling the generation of non-classical states in micron-scale devices is essential for the stable operation of integrated quantum circuits (IQCs).

Purpose of the Study:

• To propose and demonstrate a voltage-tunable micron-scale quantum entanglement device.
• To achieve significant control over non-classical light generation within integrated photonic systems.

Main Methods:

• Embedding voltage-tunable quantum emitters (QEs) into the hotspot of a metal nanostructure (MNS).
• Utilizing QE-MNS coupling to induce Fano resonance in the nonlinear response, enhancing and controlling nonlinearity.
• Leveraging voltage-induced tuning of QE level-spacing for precise control over nonlinearity.

Main Results:

• Demonstrated a micron-scale quantum entanglement device with voltage-tunable nonlinearity.
• Achieved control over non-classicality generation spanning several orders of magnitude (up to 5 orders of magnitude modulation depth).
• Showcased continuous on/off switching of non-classicality using millielectronvolt (meV) voltage tuning.

Conclusions:

• The proposed device offers a novel method for controlling non-classical light generation in IQCs.
• Voltage-tunable quantum emitters coupled to metal nanostructures provide a powerful platform for integrated quantum optics.
• This technology enables robust and efficient operation of future integrated quantum circuits.