Sun Y, Cone R L, Bigot L, Jacquier B
Department of Physics, University of South Dakota, Vermillion, SD 57069, USA.
Opt Lett. 2006 Dec 1;31(23):3453-5. doi: 10.1364/ol.31.003453.
We show that rare-earth (RE-) doped glasses can have homogeneous linewidths as narrow as 287 kHz at (4)He temperatures. This is far narrower than others reported in glasses in the same temperature range and is suitable for precise spectral hole burning and spatial-spectral holographic applications. It is known that cw spectral hole burning linewidth measurements of RE ions in glasses are hindered by the presence of spectral diffusion but, even in glasses, application of a magnetic field can freeze out RE spin-spin interactions responsible for spectral diffusion and isolate the remaining contribution of two-level systems (TLSs). The Er(3+):2G2S glasses have unusually low TLS contributions, making it possible to study the real homogeneous linewidth using photon echo measurements. The contribution from TLSs is only 170 T(1.3) kHz when subjected to a field of 5 T.
我们表明，稀土（RE）掺杂玻璃在（4）He温度下可具有低至287 kHz的均匀线宽。这远比在相同温度范围内玻璃中报道的其他线宽窄得多，适用于精确的光谱烧孔和空间光谱全息应用。众所周知，玻璃中RE离子的连续波光谱烧孔线宽测量受到光谱扩散的阻碍，但是即使在玻璃中，施加磁场也可以冻结导致光谱扩散的RE自旋 - 自旋相互作用，并分离出二能级系统（TLS）的剩余贡献。Er(3+):2G2S玻璃具有异常低的TLS贡献，使得使用光子回波测量来研究真正的均匀线宽成为可能。当施加5 T的磁场时，TLS的贡献仅为170 T(1.3) kHz。
