A low-noise, high-SNR balanced homodyne detector for the bright squeezed state measurement in 1–100 kHz range<xref rid="cpb_29_3_034205fn1" ref-type="fn">*</xref><fn id="cpb_29_3_034205fn1"><label>*</label><p>Project supported by the National Natural Science Foundation of China (Grant Nos. 11654002, 61575114, 11874250, and 11804207), the National Key Research and Development Program of China (Grant No. 2016YFA0301401), the Program for Sanjin Scholar of Shanxi Province, China, the Program for Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, China, the Fund for Shanxi “1331 Project” Key Subjects Construction, China, and Key Research and Development Projects of Shanxi Province, China (Grant No. 201903D111001).</p></fn>

A low-noise, high-SNR balanced homodyne detector for the bright squeezed state measurement in 1–100 kHz range**

Project supported by the National Natural Science Foundation of China (Grant Nos. 11654002, 61575114, 11874250, and 11804207), the National Key Research and Development Program of China (Grant No. 2016YFA0301401), the Program for Sanjin Scholar of Shanxi Province, China, the Program for Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, China, the Fund for Shanxi “1331 Project” Key Subjects Construction, China, and Key Research and Development Projects of Shanxi Province, China (Grant No. 201903D111001).

Wang Jin-Rong¹, Wang Qing-Wei¹, Tian Long^{1, 2}, Su Jing^{1, 2}, Zheng Yao-Hui^{1, 2, †}

The SNRs of the photodetector (a) with and (b) without the DC amplication branch measured at several incident powers. The traces are pieced together from two FFT frequency windows: 1–12 kHz, 12–100 kHz. Each point is the averaged rms value of 16 measurements. The RBWs of the two windows are 30 Hz and 100 Hz, respectively.