High-Resolution Single Photon Level Storage of Telecom Light Based on Thin Film Lithium Niobate Photonics

This study presents an experimental analysis of high-resolution single photon buffers based on low-loss thin film lithium niobate (TFLN) photonic devices operating at room temperature. While dynamically controlling writing and reading operations within picosecond timescales poses a challenge, the devices are capable of resolving 102.8 +/- 4.6 ps time step with -0.89 dB loss per round-trip and 197.7 +/- 6.6 ps time steps with -1.29 dB loss per round-trip, respectively. These results imply that the devices are at the cutting edge of on-chip technology, performing in the current state of the art at the single photon level. Both of the single photon buffers do not introduce any detrimental effects and provide a high signal-to-noise ratio (SNR). The room-temperature, low-loss, and voltage-controlled TFLN buffers combine scalable architecture with relatively high buffering capacity in the sub-nanosecond regime and are expected to unlock many novel photonics applications such as temporally multiplexed single photon sources.