Goto Hayato, Nakamura Satoshi, Ichimura Kouichi
Frontier Research Laboratory, Corporate Research & Development Center, Toshiba Corporation, 1, Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, 212-8582, Japan.
Opt Express. 2010 Nov 8;18(23):23763-75. doi: 10.1364/OE.18.023763.
We propose an experimental method with which all the following quantities can be determined separately: the intracavity loss and individual cavity-mirror transmittances of a monolithic Fabry-Perot cavity and furthermore the coupling efficiency between the cavity mode and the incident light. It is notable that the modified version of this method can also be applied to whispering-gallery-mode cavities. Using this method, we measured the intracavity losses of monolithic Fabry-Perot cavities made of Pr3+:Y2SiO5 at room temperature. The knowledge of the intracavity losses is very important for applications of such cavities, e.g., to quantum information technologies. It turns out that fairly high losses (about 0.1%) exist even for a sample with extremely low dopant concentration (2×10(-5) at. %). The experimental results also indicate that the loss may be mainly due to the bulk loss of Y2SiO5 crystal. The bulk loss is estimated to be 7×10(-4) cm(-1) (0.003 dB/cm) or lower.
我们提出了一种实验方法，利用该方法可以分别测定以下所有量：单片法布里-珀罗腔的腔内损耗和各个腔镜的透过率，此外还能测定腔模与入射光之间的耦合效率。值得注意的是，该方法的改进版本也可应用于回音壁模式腔。使用这种方法，我们在室温下测量了由Pr3+:Y2SiO5制成的单片法布里-珀罗腔的腔内损耗。腔内损耗的知识对于此类腔的应用非常重要，例如在量子信息技术中。结果表明，即使对于掺杂浓度极低（2×10(-5)原子%）的样品，也存在相当高的损耗（约0.1%）。实验结果还表明，损耗可能主要归因于Y2SiO5晶体的体损耗。体损耗估计为7×10(-4) cm(-1)（0.003 dB/cm）或更低。
