High-intensity spatial-mode steerable frequency up-converter toward on-chip integration
Haizhou Huang, Huaixi Chen, Huagang Liu, Zhi Zhang, Xinkai Feng, Jiaying Chen, Hongchun Wu, Jing Deng, Wanguo Liang, Wenxiong Lin
Abstract
Integrated photonic devices are essential for on-chip optical communication, optical-electronic systems, and quantum information sciences. To develop a high-fidelity interface between photonics in various frequency domains without disturbing their quantum properties, nonlinear frequency conversion, typically steered with the quadratic (χ2) process, should be considered. Furthermore, another degree of freedom in steering the spatial modes during the χ2 process, with unprecedent mode intensity is proposed here by modulating the lithium niobate (LN) waveguide-based inter-mode quasi-phase-matching conditions with both temperature and wavelength parameters. Under high incident light intensities (25 and 27.8 dBm for the pump and the signal lights, respectively), mode conversion at the sum-frequency wavelength with sufficient high output power (−7 – 8 dBm) among the TM<sub>01</sub>, TM<sub>10</sub>, and TM<sub>00</sub> modes is realized automatically with characterized broad temperature (Δ<italic>T</italic> ≥ 8 °C) and wavelength windows (Δ<italic>λ</italic> ≥ 1 nm), avoiding the previous efforts in carefully preparing the signal or pump modes. The results prove that high-intensity spatial modes can be prepared at arbitrary transparent wavelength of the χ2 media toward on-chip integration, which facilitates the development of chip-based communication and quantum information systems because spatial correlations can be applied to generate hyperentangled states and provide additional robustness in quantum error correction with the extended Hilbert space.