Proposal for a continuous wave laser with linewidth well below the standard quantum limit

  title={Proposal for a continuous wave laser with linewidth well below the standard quantum limit},
  author={Chenxu Liu and Maria Mucci and Xi Cao and M. V. Gurudev Dutt and Michael J. Hatridge and David Pekker},
  journal={Nature Communications},
Due to their high coherence, lasers are ubiquitous tools in science. We show that by engineering the coupling between the gain medium and the laser cavity as well as the laser cavity and the output port, it is possible to eliminate most of the noise due to photons entering as well as leaving the laser cavity. Hence, it is possible to reduce the laser linewidth by a factor equal to the number of photons in the laser cavity below the standard quantum limit. We design and theoretically analyze a… 

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