论文标题
自由空间中的加速和减速时空光波包
Accelerating and decelerating space-time optical wave packets in free space
论文作者
论文摘要
尽管现在可以使用大量技术来控制光波数据包的组速度，但是很少有选择可以创建加速或减速的波数据包，其组速度沿传播轴的变化而变化。在这里，我们表明，每个波长与规定的空间带宽相关联的“时空”波数据包可以实现自由空间中的光学加速度和减速。用精确的时空结构赋予该领域，会导致群体速度的变化高达$ \ sim c $，在$ \ sim20 $毫米的自由空间中观察到的距离，这至少代表了至少$ \ sim4 $ sim4 $ sim4 $范围，而不是x波和通风的脉冲。实施的加速度原则上与初始组速度无关，我们已经在山间和闪光度方案中验证了这种效果。
Although a plethora of techniques are now available for controlling the group velocity of an optical wave packet, there are very few options for creating accelerating or decelerating wave packets whose group velocity varies controllably along the propagation axis. Here we show that `space-time' wave packets in which each wavelength is associated with a prescribed spatial bandwidth enable the realization of optical acceleration and deceleration in free space. Endowing the field with precise spatio-temporal structure leads to group-velocity changes as high as $\sim c$ observed over a distance of $\sim20$ mm in free space, which represents a boost of at least $\sim4$ orders of magnitude over X-waves and Airy pulses. The acceleration implemented is in principle independent of the initial group velocity, and we have verified this effect in both the subluminal and superluminal regimes.
