公开(公告)号：US4728165A

公开(公告)日：1988-03-01

申请号：US927892

申请日：1986-11-05

申请人： Richard C. Powell ,  Edward G. Behrens ,  Frederic M. Durville

发明人： Richard C. Powell ,  Edward G. Behrens ,  Frederic M. Durville

IPC分类号： G03H1/02 ,  G03H1/28 ,  G03C1/72

CPC分类号： G03H1/02 ,  G03H1/28 ,  G03H2001/026 ,  G03H2001/0268 ,  G03H2240/26 ,  G03H2260/36 ,  Y10S359/90

摘要： A method is disclosed for producing a superimposed fast transient grating on a permanent holographic grating which provides high scattering ability, fast modulation response times, and the capability of writing and erasing signals therein. A glass host is doped with trivalent rare earth ions, and is then placed in the crossed field of two coherent radiation beams to resonantly pump the trivalent rare earth ions at a frequency in resonance with one of the absorption transitions thereof. This produces two types of laser induced gratings, a transient population grating associated with the excited rare earth ions, and a permanent holographic grating associated with a structural modification of the glass host. The superposition of these gratings result in a four wave mixing signal with enhanced strength and the capability of amplitude or frequency modulation. These superimposed gratings have applications involving phase conjugation and other types of optical signal processing and also provide a new method for probing the local structural properties of amorphous materials.

摘要翻译： 公开了一种用于在永久全息光栅上产生叠加的快速瞬态光栅的方法，其提供高散射能力，快速调制响应时间，以及在其中写入和擦除信号的能力。 玻璃主体掺杂有三价稀土离子，然后放置在两个相干辐射束的交叉场中，以与其吸收转变之一谐振的频率共振地泵浦三价稀土离子。 这产生两种类型的激光感应光栅，与激发的稀土离子相关联的瞬态群体光栅，以及与玻璃主体的结构修改相关联的永久全息光栅。 这些光栅的叠加导致具有增强的强度和振幅或频率调制能力的四波混频信号。 这些叠加的光栅具有涉及相位共轭和其他类型的光信号处理的应用，并且还提供了一种用于探测无定形材料的局部结构特性的新方法。