Remanent switching of Bloch-polaritons

该项目的目标是开发能够在室温和更高温度下实现(剩余和持久的)量子力学状态的非易失性切换的光子结构。这是通过发展结构来实现的，这种结构允许光子布洛赫表面模与激子的电子系统耦合，形成所谓的布洛赫极化子。通过共振激发，将实现极化子凝聚体的传播。这些极化子的光子成分确保了数百微米的远距离传播和高表面灵敏度。这种高的表面敏感性将被利用，以控制和改变Bloch-Polariton的性质，例如，能量、动量、自旋和波函数的相位，借助于将被集成在结构表面的铁电材料。通过施加电脉冲，将在铁电材料内产生或更确切地说改变铁电极化。这种偏振与相邻的氧化锌层的压电性耦合导致了光子结构的光学性质的改变，从而改变了Bloch-Polariton的光学性质。对Bloch-Polariton性质变化的证明将通过光学方法来完成。因此，该方法允许状态的电写入和光学读出。此外，在这个项目中，将详细研究Bloch-Polariton的性质，如它们与环境的相互作用，它们的弛豫和散射行为，以及控制它们特性的可能性。在文献中没有讨论这些特性，并且特别感兴趣，因为Bloch-Polariton对于实现基于偏振子的器件和集成光学是非常有希望的，因为它们在其传播长度和在低温下的操作方面不表现出限制。

The aim of the project is to develop photonic structures which allows a non-volatile switching (remanently and persistently) of a quantum mechanical state at room temperature and above. This is reached by developing structures which allows the coupling of the photonic Bloch surface modes with the electronic system of the excitons, forming so-called Bloch-polaritons. By means of resonant excitation a propagating polariton condensate will be realized. The photonic component of these polaritons ensures the long range propagation over several hundreds of micrometre and a high surface sensitivity. This high surface sensitivity will be exploite in order to control and change the properties of the Bloch-polaritons, e.g. energy, momentum, spin and phase of the wave function, by means of a ferroelectric material which will be integrated at the surface of the structure. By applying an electric pulse, a ferroelectric polarisation within the ferroelectric material will be created or rather changed. The coupling of this polarisation with the piezoelectric one of an adjoin ZnO layer leads to a change of the optical properties of the photonic structure and therewith of the Bloch-polaritons. The proof of this change of the properties of the Bloch-polaritons will be done by optical methods. Therefore, this approach allows the electrically writing and the optical read-out of a state. Furthermore, the properties of Bloch-polaritons as their interaction with their environment, their relaxation and scattering behaviour as well as the possibilities to control their properties will be investigated in detail within this project. These properties are not discussed in the literature and are of special interest since Bloch-polaritons are very promising for the realization of devices and integrated optics based on polaritons since they do not exhibit limitations with respect to their propagation length and an operation at low temperatures.