RUI, OP: Space-Variant Polarization States of Light

光束的使用，就像激光一样，对现代技术的发展产生了革命性的影响，从电话通信到激光手术，从电话通信到激光手术，信息都是通过光纤传输的，激光手术将高强度的光传输到组织的小区域。这些技术利用光的颜色或能量。光的另一个特性是它的偏振，肉眼是看不见的，但间接地可以看到，例如，通过某些类型的3D电影或偏振太阳镜的视觉效果。这项研究将涉及准备光束的偏振，像在图像中一样，光束的偏振在点到点之间变化。这种偏振将被编码到单个光子(光的“粒子”)上。光子可以携带大量信息，同时又是量子的，或者说是完整的。利用光和物质的量子方面的技术有可能将当前的通信技术升级到速度和容量大幅提高的技术。极化还有望成为操纵手性分子或开瓶器状分子的工具。这包括大多数有机分子，包括DNA(双螺旋)。这项研究将检验最近的理论，这些理论预测，光的偏振可以用来将手性分子分离成从特定的一端观察时顺时针或逆时针旋转的分子(例如，DNA总是以一种方向螺旋，而不是另一种)。这是药物合成中重要的一步，因为螺旋状的分子可以治愈，而螺旋状的分子可能会造成伤害。这项研究将涉及本科生，向他们介绍科学过程，同时培训他们现代光子技术。具有空间可变偏振的光态类似于纠缠量子态，因为两者都是不可分离的。因此，空间可变偏振态非常适合用于量子信息。它们通过以下方式为光子的量子态增加了更高的维度：它们需要光的偏振(在两个维度)和横向空间模式(原则上，增加无限多个额外维度)的不可分离的叠加。因此，空间模式为将量子信息编码到单个光子上的空间增加了更高的维度。我们已经开发了编码和解码这些状态的技术，由于它们的空间变化的偏振可以通过成像技术来诊断。这项研究将研究在偏振和空间模式中纠缠的光子对的空间，以及这些态将编码的非局域空间变化的偏振图像。同时，携带空间可变偏振的强光将被用来研究一种预测但尚未证实的新光力，它影响手性分子的方式，使其通过惯用手分离分子。也就是说，光产生了一个场梯度，它施加的力对于右手和左手手性手性是相反的符号。这种基本上与旋光性有关的新作用力在复杂有机分子的化学合成中可能是重要的，在化学合成中，人们希望将一个手性与另一个手性分开。

The use of beams of light, like laser beams, has been transformative in the development of modern technologies, from telephone communications where information is encoded in the light traveling through fibers, to laser surgery where high light intensity is delivered to small areas of tissue. These technologies exploit light's color or energy. Yet another property of light is its polarization, which is invisible to the unaided eye, but seen indirectly, for example, through the visual effects of some types of 3D movies or in polarizing sunglasses. This research will involve preparing light beams with polarization that varies from point to point across the beam, like in an image. This polarization will be encoded onto individual photons (the "particles" of light). Photons can carry a lot of information while at the same time being quantum, or whole. Technologies that harness the quantum aspects of light and matter have the potential to upgrade current communication technologies to ones with substantially increased speed and capacity. Polarization also holds promise as a tool to manipulate molecules that are chiral, or corkscrew-like. This encompasses most organic molecules, including DNA (the double helix). This research will test recent theories which predict that the polarization of light can be used to segregate chiral molecules into those that spiral clockwise or counterclockwise when viewed from a particular end (DNA always spirals one way but not the other, for example). This is an important step in the synthesis of medicines because molecules that spiral one way could cure while those that spiral the other way could cause harm. This research will involve undergraduates, introducing them to the scientific process while training them in modern photonic technologies. States of light that have spatially variable polarization are similar to entangled quantum states in that both are non-separable. Thus, space-variant-polarization states are well suited for use in quantum information. They add higher dimensions to the quantum states of photons in the following ways: they entail non-separable superpositions of polarization (in two dimensions) and transverse spatial modes of light (in principle, adding an infinite number of additional dimensions). Thus, spatial modes add a higher dimensionality to the space in which to encode quantum information onto single photons. We have developed techniques that encode and decode these states, which due to their space-variant polarization can be diagnosed by imaging techniques. This research will investigate the space of photon pairs entangled in polarization and spatial modes and the nonlocal space-variant polarization images that those states will encode. In parallel, intense beams carrying space-variant polarization will be used to investigate a predicted but yet unconfirmed new light force, which affects chiral molecules in such a way that it segregates the molecules by their handedness. That is, the light creates a field gradient that applies a force that is of opposite sign for right and left handed chiralities. This new force, fundamentally related to optical activity, could be of importance in the chemical synthesis of complex organic molecules, where it is desirable to separate one chirality from the other.