论文标题
钛中钛锂波导钛中的低温电光调节
Cryogenic electro-optic modulation in titanium in-diffused lithium niobate waveguides
论文作者
论文摘要
Niobate锂是集成量子光学元件的有前途的平台。在这个平台中，我们旨在通过结合超导单个光子探测器和调节器来有效地操纵和检测量子状态。超导单个光子检测器的低温操作决定了在相同的工作条件下电气调节器的优化。为此，我们表征了一个相调节器，定向耦合器和在环境和低温温度下的极化转换器。这些调节器的操作电压$ v_ {π/2} $增加，由于相位调节器的电磁效应降低了74％，方向耦合器的84％，偏振转换器的35％低于8.5 $ \，\\，\ mathrm {k} $。相调节器保留其宽带性质，并在特征波长范围内调节光。定向耦合器的无偏条状态通过85 $ \，\ mathrm {nm} $的波长移动变化，同时将设备冷却至5 $ \，\ Mathrm {k} $。极化转换器使用周期性的波动来对两个正交极化。冷却至5 $ \，\ mathrm {k} $时，所使用的极点的变化波长更改了112 $ \，\ mathrm {nm} $
Lithium niobate is a promising platform for integrated quantum optics. In this platform we aim to efficiently manipulate and detect quantum states by combining superconducting single photon detectors and modulators. The cryogenic operation of a superconducting single photon detector dictates the optimisation of the electro-optic modulators under the same operating conditions. To that end, we characterise a phase modulator, directional coupler, and polarisation converter at both ambient and cryogenic temperatures. The operation voltage $V_{π/2}$ of these modulators increases due to the decrease of the electro-optic effect by 74% for the phase modulator, 84% for the directional coupler and 35% for the polarisation converter below 8.5$\,\mathrm{K}$. The phase modulator preserves its broadband nature and modulates light in the characterised wavelength range. The unbiased bar state of the directional coupler changed by a wavelength shift of 85$\,\mathrm{nm}$ while cooling the device down to 5$\,\mathrm{K}$. The polarisation converter uses periodic poling to phasematch the two orthogonal polarisations. The phasematched wavelength of the used poling changes by 112$\,\mathrm{nm}$ when cooling to 5$\,\mathrm{K}$
