Experimental Studies on Geometrical Properties of Wave Propagation

我们研究了一维波传播的几何特征和量子Zeno效应。波幅的旋量行为、规范变换、Bloch型方程和Lorentz群Berry位相等几何成分被简化为一维波传播的动力学由(2*1)维Lorentz群或SL(2，R)描述。另一方面，量子Zeno效应是对量子动力学的抑制或抑制。这种效应是由退相干引起的，这也可以用SL(2，R)-动力学来描述。[波传播中的量子Zeno效应]在偏振光学中，像偏振片这样的耗散元件可以有效地破坏相干并诱导量子Zeno效应。[经典系统中的量子Zeno效应]人们发现经典系统中存在量子Zeno效应。我们用电路实验验证了经典的Zeno效应。[量子Zeno效应的自旋操纵]我们提出了一种新的光学泵浦方案，通过它可以控制原子在快速泵浦极限下的自旋运动，而不需要吸收光子。这一现象可以用量子Zeno效应和无相互作用测量来解释，通常两态系统中的量子Zeno效应意味着SL(2，R)动力学对SU(2)动力学的控制。但可能会发现SL(2，R)动力学由SL(2，R)动力学控制的情况。

We investigated geometrical features of 1D wave propagation and the quantum Zeno effect. The geometrical ingredients, such as spinor-like behavior of wave amplitudes, gauge transformations, Bloch-type equations, and Lorentz-group Berry phases, are reduced to the fact that the dynamics of 1D wave propagation is described by the (2*1)-dimensional Lorentz group or SL(2, R). On the other hand, the quantum Zeno effect is the suppression or the inhibition of the quantum dynamics. The effect is induced by the decoherence, which can be described also by the SL(2, R)-dynamics.[Quantum Zeno Effect in Wave Propagation] In polarization optics, dissipative elements such as polaroids can effectively destroy the coherence and induce the quantum Zeno effect.[Quantum Zeno Effect in Classical Systems] It has been found that the quantum Zeno effect emerges in the classical system. Experiments on electric circuits have been carried out to verify the classical Zeno effect.[Spin Manipulation with Quantum Zeno Effect] We have presented a novel optical pumping scheme by which atomic spin motion can be controlled without photon absorption in the fast pumping limit. The phenomenon can be understood in term of the quantum Zeno effect and the interaction-free measurement.The quantum Zeno effects in usual two-state system means the control of SU(2) dynamics by the SL(2, R) dynamics. But it might be possible to find cases where the SL(2, R) dynamics is controlled by the SL(2, R) dynamics.