Interstitial nitrogen molecule CMOS-fabricated quantum memory for frequency and bandwidth conversion
ORAL
Abstract
The development of hybridized quantum devices and networks necessitate full control of photon spectral properties, and in particular, the conversion of single photon frequency and spectral bandwidth. One approach to spectral conversion utilizes a Λ-style Raman quantum memory, which allows for wide frequency conversion, bandwidth manipulation, and on-demand readout. In this system, a single photon detuned from the excited state is mapped to a collective excitation by a write control pulse. A classical retrieval control pulse annihilates the collective excitation and generates a single output photon with spectral properties dependent on the characteristics of the classical pulse. We propose a Raman quantum memory in a CMOS-compatible photonic integrated circuit platform using interstitial nitrogen molecules trapped in silicon nitride (N2:SiN) waveguides. With a narrow linewidth vibrational mode at 70 THz, interstitial N2 defects allow for room temperature operation and the storage of broadband photons.
By solving the optical Maxwell-Bloch equations, storage and retrieval efficiencies are calculated across control pulse energy, waveguide interaction length, and photon wavelength. We predict large storage efficiencies for broadband visible photons with nanojoule control pulse energies and centimeter-long waveguides. With the long interaction lengths of the silicon nitride waveguides, dispersion engineering is essential to both increase memory performance and suppress four-wave mixing noise. Using finite-element simulations, we calculate frequency-dependent phase matching for various waveguide geometries and demonstrate various phase matching conditions allowing visible-telecom frequency conversion. Furthermore, we discuss the effect of group velocity mismatch and group velocity dispersion on memory performance. Finally, we show initial experimental results towards the storage and retrieval of THz photons in a N2:SiN quantum memory.
By solving the optical Maxwell-Bloch equations, storage and retrieval efficiencies are calculated across control pulse energy, waveguide interaction length, and photon wavelength. We predict large storage efficiencies for broadband visible photons with nanojoule control pulse energies and centimeter-long waveguides. With the long interaction lengths of the silicon nitride waveguides, dispersion engineering is essential to both increase memory performance and suppress four-wave mixing noise. Using finite-element simulations, we calculate frequency-dependent phase matching for various waveguide geometries and demonstrate various phase matching conditions allowing visible-telecom frequency conversion. Furthermore, we discuss the effect of group velocity mismatch and group velocity dispersion on memory performance. Finally, we show initial experimental results towards the storage and retrieval of THz photons in a N2:SiN quantum memory.
*This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. SNL is a multimission laboratory managed and operated by NTESS under DOE NNSA contract DE-NA-0003525.
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Presenters
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Kathleen B Oolman
- Sandia National Laboratories