Quantum metasurface for multiphoton interference and state reconstruction

Area of Science:

• Quantum optics
• Nanophotonics
• Metasurface technology

Background:

• Metasurfaces offer advanced flat-optics devices but are underutilized in quantum applications.
• Nanophotonic structures enable novel optical functionalities at the subwavelength scale.

Purpose of the Study:

• To explore the use of all-dielectric metasurfaces for quantum applications.
• To demonstrate subwavelength manipulation and measurement of multiphoton quantum states.
• To enable robust reconstruction of quantum state properties.

Main Methods:

• Utilizing all-dielectric metasurfaces with resonant nanophotonic structures.
• Achieving nonclassical multiphoton interference at the subwavelength scale.
• Employing nonlocal photon correlation measurements with polarization-insensitive detectors.

Main Results:

• Simultaneous imaging of multiple quantum state projections using a single metasurface.
• Robust reconstruction of amplitude, phase, coherence, and entanglement of multiphoton states.
• Experimental reconstruction of one- and two-photon states, with theoretical scalability to higher photon numbers.

Conclusions:

• All-dielectric metasurfaces are feasible for ultrathin quantum metadevices.
• These devices can manipulate and measure multiphoton quantum states.
• Potential applications include free-space quantum imaging and communications.