Fully Collective Superradiant Lasing with Vanishing Sensitivity to Cavity Length Vibrations

Area of Science:

• Atomic Physics
• Quantum Optics
• Metrology

Background:

• Realizing continuous-wave (CW) active atomic clocks has been challenging due to parasitic heating from spontaneous emission during atomic repumping.
• Existing collective two-level models lack a generic lasing threshold, hindering advancements in atomic clock technology.

Purpose of the Study:

• To propose a novel solution for CW active atomic clocks by mitigating parasitic heating.
• To overcome the limitations of collective two-level models in achieving a lasing threshold.

Main Methods:

• Replaced random spontaneous emission with coupling to an auxiliary cavity for collective atomic repumping.
• Utilized multilevel atoms to enable collective pumping and decay on distinct transitions, overcoming the lasing threshold restriction.
• Analyzed system performance using relevant atomic parameters.

Main Results:

• Demonstrated a system capable of producing a CW superradiant laser with an O(100 μHz) linewidth.
• Identified a potential operating regime with cavity length vibration sensitivity below O(10⁻¹⁴/g).
• Found parameter values where vibration sensitivity completely vanishes, even at steady state.

Conclusions:

• The proposed method effectively addresses parasitic heating issues in CW atomic clocks.
• Multilevel atoms in a collective cavity-coupled system enable a lasing threshold, paving the way for advanced atomic clocks.
• The system offers unprecedented low vibration sensitivity, crucial for high-precision timekeeping.