Xinzhong

Bio: Xinzhong is an academic researcher. The author has contributed to research in topics: Laser linewidth & Injection seeder. The author has an hindex of 1, co-authored 1 publications receiving 3 citations.

Narrow linewidth distributed-feedback laser with low relative intensity noise

Abstract: We fabricated a low relative intensity noise (RIN) narrow linewidth semiconductor laser module. The structure of the monolithic integrated laser chip is asymmetric phase-shifted DFB structure with the length of 1000-µm. The maximum output power reaches 26mW when the driving current is 200mA. The narrowest linewidth reaches about 35 kHz with the driving current at 150mA, and the RIN is lower than −165 dB/Hz for the frequency offset from 0.1GHz to 20 GHz in the whole current tuning range from 40 mA to 200 mA. This laser module has wide application prospects for optical sensing, digital coherent and analog communication areas.

Advances in narrow linewidth diode lasers

Abstract: The era of smart travel has arrived, and the need for high precision lidar detection technology is increasing. With the advantages of high resolution, a strong anti-active jamming ability, small volume, light weight, and low cost, new solid-state lidars can meet the requirements of intelligent cars in the future. A narrow linewidth diode laser is an ideal light source of solid-state lidars. The progress and development of narrow linewidth diode laser techniques can greatly improve the application of solid-state lidars. In this paper, the technology and development is described in detail. In addition, the design ideas, key fabrication technologies, and optical characteristics of various narrow linewidth diode lasers are analyzed and discussed. Finally, the developments of narrow linewidth diode lasers are proposed.

Design Methodology for Reducing RIN Level in DFB Lasers

Abstract: The relative intensity noise (RIN) characteristics in distributed feedback (DFB) lasers are analyzed theoretically by proposing a new methodology. In addition to temperature variation (T), the effect of other model parameters such as injection current (Iinj), active layer volume (V), spontaneous emission (βsp) and gain compression (ε) factors on RIN characteristics is investigated. The numerical simulations shows, the peak RIN level can be reduced to around –150 dB/Hz, while relaxation oscillation frequency (ROF) is shifted towards 5.6 GHz. In addition, the RIN level is increased with temperature by the rate of 0.2 dB/oC and ROF is reduced by the rate of 0.018 GHz/oC. Results show, the low RIN level can be obtained by selecting model parameters reasonably.

Principles, Measurements and Suppressions of Semiconductor Laser Noise—A Review

Abstract: Semiconductor lasers are widely used in incoherent/coherent optical communications, optical fiber sensing, and lidar due to their small size, high efficiency, and immunity to vibrations. To support the continuous evolution of these high-performance application systems, the noise characteristics of semiconductor lasers play a key role and the noise levels need to be reduced to unprecedentedly low values (such as quantum limit). In this paper, a comprehensive overview on the principles, measurements, and suppressions of semiconductor laser noises are provided. First, we introduce the analysis models and key performance indicators of semiconductor lasers related to noise. Then, different noise measurement systems are investigated for semiconductor lasers and the noise characteristics are fully analyzed. Next, the noise suppression methods towards semiconductor lasers are demonstrated from three aspects: the chip structures, the external cavity optical feedback technology and the driving and controlling circuits. Finally, we summarize the recent advances on the noise measurement and suppression of semiconductor laser, future prospects are also discussed.