High energy, high repetition rates laser with excellent beam quality are fundamental components for LiDAR. In particular, high pulse energy is benefit for long distance range imaging. Narrow pulse width and high repetition rates are benefit for high resolution and high refresh rate operation of LiDAR. However, increasing the laser repetition rates will cause the pulse energy decreasing and the pulse width expanding. In order to achieve the requirements at the same time, we propose a 885 nm laser diode end-pumped RTP Q-switched Nd:YAG laser. Pulse pumping scheme was used to avoid heat accumulation. With a master oscillator power amplifier (MOPA) system, 40.5 mJ, 7.5 ns of 1064 nm pulses were obtained at 2 kHz. The beam quality factor M 2 was measured as 1.60/1.51. Moreover, by frequency doubling with a LBO crystal, 16.4 mJ, 6.5 ns of 532 nm laser with the M 2 factor of 1.52 and 1.50 was obtained. The 1064 and 532 nm pulses are suitable for avalanche photodiode arrays LiDAR and streak tube imaging LiDAR, respectively. The laser system is shown to accomplish high stability from temperature of −10 C to 30 C and vibration frequency of 10 to 100 Hz.

Nanocomposite films with a small loading of two-dimensional Bi2Te3@Al2O3 hexagonal nanoplates exhibit a high dielectric constant of 140 and relatively low dielectric loss of 0.05 at 1 kHz.

High energy, sub‐nanosecond, single longitudinal mode (SLM) pulse is especially preferred for LiDAR application. In this paper, a kHz‐level sub‐nanosecond electro‐optical Q‐switched Nd:YVO4 laser of SLM operation for remote sensing was demonstrated. By utilizing a compact resonator with a Volume Bragg Grating as output coupler, maximum SLM output power of 1.08 W and pulse width of 919 ps was obtained at 10 kHz. Moreover, we proposed a theoretical model to calculate the multimode threshold of the VBG‐coupled cavity. The longitudinal mode characteristics at four different cavity lengths were investigated experimentally and the results match well with the numerical simulations, which validates the theory. We expected the method could help to guide VBG‐coupled cavity design and construction.

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