Birefringence in optical fibers poses a challenge to controllably delivering polarized light. Strain-induced birefringence caused by bends in the fiber, vibrations, or a large temperature gradient can significantly alter the polarization, making it particularly difficult to deliver polarization states to low-temperature environments by fiber. In this paper, we investigate the transmission of polarized light through a fiber and discuss a method we have developed for delivering arbitrarily polarized light to the base stage of a dilution refrigerator using a standard optical fiber. We have created a compact, cryogenic optical system to identify the polarization of the delivered light, while room-temperature waveplates and a mathematical fiber model are used to fully characterize and compensate for the fiber's birefringent effects. We show here that we are able to deliver horizontal, vertical, diagonal, anti-diagonal, right circular, and left circular polarization states to milli-Kelvin temperatures, with state fidelities of greater than 0.96 being achieved in all cases. Additionally, we demonstrate that we can deliver randomly selected elliptical states through a standard fiber to the refrigerator. This opens up new opportunities for fiber-based optical experiments using polarized light, such as quantum information experiments using quantum states encoded in the polarization of single photons.

中文翻译：

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稀释制冷机中光纤传输光的全偏振控制

光纤中的双折射对可控地传输偏振光提出了挑战。由光纤弯曲、振动或大温度梯度引起的应变引起的双折射会显着改变偏振，使得光纤很难将偏振态传递到低温环境。在本文中，我们研究了偏振光通过光纤的传输，并讨论了我们开发的一种方法，该方法使用标准光纤将任意偏振光传输到稀释制冷机的基础阶段。我们创建了一个紧凑的低温光学系统来识别传输光的偏振，同时使用室温波片和数学光纤模型来完全表征和补偿光纤的双折射效应。我们在这里展示了我们能够将水平、垂直、对角线、反对角线、右圆和左圆偏振态提供到毫开尔文温度，在所有情况下都实现了大于 0.96 的状态保真度。此外，我们证明了我们可以通过标准光纤将随机选择的椭圆状态传送到冰箱。这为使用偏振光的基于光纤的光学实验开辟了新的机会，例如使用编码在单光子偏振中的量子态的量子信息实验。我们证明我们可以通过标准光纤将随机选择的椭圆状态传送到冰箱。这为使用偏振光的基于光纤的光学实验开辟了新的机会，例如使用编码在单光子偏振中的量子态的量子信息实验。我们证明我们可以通过标准光纤将随机选择的椭圆状态传送到冰箱。这为使用偏振光的基于光纤的光学实验开辟了新的机会，例如使用编码在单光子偏振中的量子态的量子信息实验。