Coherent Parameter Measurement Based on Partial Coherent Envelope Demodulation  

作　　者：Chaoze Zhang Laiyang Dang Tianyu Guan Yuqin Mao Ligang Huang Tao Zhu Chaoze Zhang;Laiyang Dang;Tianyu Guan;Yuqin Mao;Ligang Huang;Tao Zhu(Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing, China)

机构地区：[1]Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing, China

出　　处：《Optics and Photonics Journal》2023年第6期133-139,共7页光学与光子学期刊（英文）

摘　　要：The key parameters of laser energy concentration and coherence can be characterized by laser linewidth, which determines the detection range, measurement resolution and signal-to-noise ratio of laser precision measurement technology. Up to now, the laser linewidth is mainly measured by the energy distribution width in the frequency domain, but the coherence of the laser has not been measured or characterized directly. In this work, we propose the concept of coherent linewidth based on the coherent envelope of delayed self-heterodyne detection to directly characterize the time-frequency coherence of lasers. In the proof-of-concept experiment, we obtain the coherence coefficient through the Fourier transform of the partial coherence envelope, and then measure the coherence linewidth of the laser. The measured coherent linewidth is smaller than the traditional integral linewidth and larger than the intrinsic Lorentzian linewidth, indicating that the coherent linewidth is less affected by low-frequency 1/f noise. The concept of coherent linewidth proposed in this article can serve as a candidate method for directly characterizing the coherence of narrow linewidth lasers. .The key parameters of laser energy concentration and coherence can be characterized by laser linewidth, which determines the detection range, measurement resolution and signal-to-noise ratio of laser precision measurement technology. Up to now, the laser linewidth is mainly measured by the energy distribution width in the frequency domain, but the coherence of the laser has not been measured or characterized directly. In this work, we propose the concept of coherent linewidth based on the coherent envelope of delayed self-heterodyne detection to directly characterize the time-frequency coherence of lasers. In the proof-of-concept experiment, we obtain the coherence coefficient through the Fourier transform of the partial coherence envelope, and then measure the coherence linewidth of the laser. The measured coherent linewidth is smaller than the traditional integral linewidth and larger than the intrinsic Lorentzian linewidth, indicating that the coherent linewidth is less affected by low-frequency 1/f noise. The concept of coherent linewidth proposed in this article can serve as a candidate method for directly characterizing the coherence of narrow linewidth lasers. .

关 键 词：Laser Linewidth Coherent Linewidth Coherent Envelope 

分 类 号：TN2[电子电信—物理电子学]