Studying the stability of wavelengths radiated by a gas laser

Conclusions

• 1. According to the theoretical analysis the instability of a laser of the above design for 20–30 min operation in a single TEM_00q mode amounts to ∼10⁻⁷.

• 2. The technique and equipment developed by us for measuring long-term and short-term frequency instability of a continuously-operating laser provides a resolution of (5–7) · 10⁻¹⁰ for relative measurements and of ∼7 · 10⁻⁸ for absolute measurements of wavelengths.

• 3. Under normal laboratory operating conditions the laser radiation wavelength instability amounted to ∼1.5 · 10⁻⁷ for durations of 10–15 min and to ∼1 · 10⁻⁷ for durations of 10 sec.

• 4. The laser stability is substantially raised by using an automatic frequency stabilization by means of an external (reference) thermostatically controlled resonator. Tests have shown that the radiation frequency instability under these conditions amounts to (5–8) · 10⁻⁹ for 10–15 sec and to ∼10⁻⁸ for 20–30 min. An improvement of the above equipment will probably raise the frequency stability at least tenfold.

• 5. The above results show that the laser developed by us can be used successfully with a stabilization circuit for various metrological experiments.