量子点分子中轨道Angular Momentum对光的操纵和交换
Manipulation and exchange of Light with Orbital Angular Momentum in Quantum Dot Molecules
摘要：
研究了轨道角动量激光脉冲与具有四个能级的非对称量子点分子的相互作用。我们展示了点间隧穿如何赋予不同频率之间的光学涡旋交换。我们考虑的情况下，一个弱的探测光束有一个光学涡旋，因此在中心的强度为零。隧道耦合的存在产生了一个额外的弱激光束与入射的涡旋光束相同的涡度。我们分析了初始光束的涡旋被有效地转移到所产生的光束的条件。研究了具有方位折射率和径向折射率的OAM态的拉盖尔-高斯（LG）光束在强控制光束也是OAM模的情况下的传输。结果表明，在OAM交换过程中，OAM状态的守恒性总是满足的。然而，一个异常的情况下，观察到的径向折射率诱导产生的光束，这不同于入射光束的纯LG光束的一些强度图案。给出了解析解，阐明了径向折射率对OAM光束传输特性的影响。当叠加两个最初存在的弱OAM模式时，观察到所产生的光学涡旋随着光的传播而围绕光束轴移动，从而在中心周围形成一种“星座”。这种复合脉冲的轴的偏移是由于点间隧穿效应，该效应由外部电压控制。光学角动量可以为量子技术研究固体系统增加一个新的自由度。
英文摘要：
We study the interaction of laser pulses carrying orbital angular momentum (OAM) with structural asymmetry quantum dot molecules characterized by four energy levels. We demonstrate how the inter-dot tunneling endows exchange of optical vortices between different frequencies. We consider a case where a weak probe beam has an optical vortex and thus has a zero intensity at the center. The presence of tunneling coupling generates an additional weak laser beam with the same vorticity as that of the incident vortex beam. We analyze conditions for the vortex of the initial beam to be transferred efficiently to the generated beam. The propagation of Laguerre-Gaussian (LG) beams possessing OAM states characterized by both azimuthal and radial indices is then investigated for the case where the strong control beam is also an OAM mode. It is shown that the conservation of OAM states is always satisfied over the OAM exchange process. Yet, an abnormal case is observed in which the radial index induces some intensity patterns of the generated beam which differs from a pure LG beam of incident beams. Analytical solutions are provided to elucidate such effects induced by radial indices on propagation characteristics of OAM beams. When superimposing two initially present weak OAM modes, it is observed that the resulting optical vortices move about the beam axis as the light propagates, forming a sort of "constellation" around the center. The shift in axis of such a composite pulses is due to the effect of inter-dot tunneling which is controlled by an external electric voltage. The optical angular momenta may add a new degree of freedom in the study of solid systems suitable for quantum technologies.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
