EAGER: Collaborative Research: Electrically Pumped Monolithic Bi-photon emitters

Integrated photonic systems hold promise to provide a scalable and robust platform for quantum technologies including secure quantum communications, quantum imaging, and quantum sensing. A practical quantum photonic system should monolithically integrate the sources of entangled photons with the rest of the photonic circuitry. Such sources have to be compact, monolithic and electrically pumped.

The existing solutions are bulky and require external laser pumping, which puts many practical applications out of reach. We propose a new type of bright compact monolithic source of entangled photons based on the original electrically pumped semiconductor laser heterostructure. We intend to develop the theoretical model, formulate the detailed design concept, and demonstrate efficient generation of photon pairs in the mid-infrared region of spectra.

The proposed collaborative efforts will enable a new class of the applications harnessing quantum properties of light. The two PIs will incorporate research results into graduate and undergraduate classes and their ongoing outreach effort to high school students and physics teachers. They will continue their commitment to recruiting under-represented students into STEM careers.

The proposed quantum technology research will prepare future scientists and engineers and facilitate implementation of the discoveries of the next quantum revolution into modern technologies. Technical:

Strong second order nonlinearity of III-V semiconductors can be used for production of the entangled photon states by means of cavity spontaneous parametric down conversion (SPDC) where the waveguides and other photonic integrated circuit components can be utilized to facilitate phase matching and perform quantum information processing operations. The monolithic integration of the pump laser and SPDC source of mid-infrared photon pairs is needed for practical applications and is the primary goal of our proposal.

We will develop new class of laser heterostructures which can yield high power and narrow linewidth pumps and simultaneously enable efficient parametric down conversion of laser light into photon pairs. In standard single core laser waveguides the phase matching conditions for SPDC process are virtually impossible to achieve because of normal dispersion.

The original coupled-waveguide design will be used to achieve modal phase matching required for efficient generation of the correlated photon pairs by intra-cavity SPDC. The pump photons will comprise an asymmetric super-mode with a reduced effective refractive index overcoming normal dispersion – a key enabling feature of the proposed design. The type-II intracavity SPDC will produce correlated TE and TM polarized pairs of signal and idler photons.

Theoretical description of the generation, propagation, and detection of the non-classical light states in the proposed monolithic quantum photonic structure will be developed.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.