Ultra-Low Mean-Photon-Number Measurement with Balanced Optical Heterodyne Detection

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2004,（4）
• 页码范围: 671-674
• 页数: 4页
• 语种: 英文

摘要

Determination of an ultra-low mean photon number is an important issue, either for precise optical measurement or understanding the interaction between individual atoms and photons inside an optical cavity. By utilizing a homemade balanced optical heterodyne detection system, the cw minimum measurable power of 3.6 fW has been reached, whereas the minimum mean photon number of <n> = 0.0014 in our micro-cavity with finesse of 2 × 105and optical length of 48 μm can be realized.