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We improve the output of a MOPA system that emits single-frequency high-energy optical pulses using a large mode area Er-doped fiber amplifier pumped by a cascaded Raman fiber laser with a low 150 Hz repetition frequency. It is found that the unwanted light generated in the cascaded Raman fiber laser at the same time as the pump light saps the gain of the amplifier and degrades its output characteristics. By combining the removal of unwanted light with a pulse pump technique, the pulse energy is improved from less than 1.0 mJ to 1.2 mJ with at the same time a SNR of 30 dB compared to 19 dB before the improvement. The percentage of power in the signal also improves from 61.0% to over 90.7%.

We demonstrate a master oscillator power amplifier system that emits single-frequency, high-energy optical pulses at 1539 nm using an Er, Yb:glass planar waveguide amplifier with a normalized frequency of the waveguide of 4.4. A maximum pulse energy of 9.7 mJ is observed at a repetition frequency of 500 Hz. The signal to noise ratio is 25 dB and is independent of the repetition frequency from 100 to 500 Hz. The beam quality factor M ^2 of the output is 1.03 thanks to the small normalized frequency of the planar waveguide.

The realization of cold atoms using a compact and low-power-consumption experimental setup is indispensable for cold atom experiments, including optical clocks and quantum simulations. We demonstrate the direct loading of Yb atoms into a 3D magneto-optical trap (MOT) from a dispenser atomic source without using a Zeeman slower. The power consumption of the dispenser was ∼3 W. Spectroscopy of the atomic beam from the dispenser on the 6s2 1S0–6s6p 1P1 Yb transition at 399 nm shows that the flux of the atomic beam reaches 1.4 × 1013 s−1 cm−2. We can load up to 4.1 × 107 atoms into the MOT with slowing and trapping laser powers of 20.3 and 35.0 mW, respectively. The realized cold atom system is reliable and can be adapted for experiments on alkaline earth and other alkaline earth-like atoms.