Controlling the polarization state of light at a fast speed is important in both classical and quantum regimes. Here, we present an easily integrated compact tunable linear polarization-state generator of single photons in the telecom wavelength band on a periodically poled lithium niobate on insulator (PPLNOI) chip. The linear polarization of single photons can be continuously rotated by applying a transverse electric field utilizing the electro-optic (EO) effect. With strong light confinement and the large EO coefficient in the PPLNOI ridge waveguide, dramatically reduced driving voltage and fast-speed modulation is realized. Moreover, quantum entanglement is well maintained during the switching of polarization states, as proved in the time-energy entanglement measurement. The scheme holds promise for realizing integrated quantum optics.

中文翻译：

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铌酸锂芯片上单光子的可调线性偏振态发生器

在经典方案和量子方案中，快速控制光的偏振态都很重要。在这里，我们介绍了一个在周期性极化的绝缘子上铌酸锂（PPLNOI）芯片上电信波段中单个光子的易于集成的紧凑型可调谐线性偏振态发生器。通过利用电光（EO）效应施加横向电场，可以连续旋转单个光子的线性极化。通过在PPLNOI脊形波导中进行强光限制和大EO系数，可以显着降低驱动电压并实现快速调制。此外，如时间-能量纠缠测量中所证明的，在极化状态的切换期间量子纠缠得到了很好的维持。该方案有望实现集成量子光学。