Quenching Quantum Phase Noise: Correlated Spontaneous Emission versus Phase Locking
Abstract
Measuring the phase dynamics of the beat note in the output of a HeNe Zeeman laser, we (i) unravel the interplay of phase locking and correlated spontaneous emission, (ii) observe the phase-diffusion noise reduced to 114 of the Schawlow-Townes quantum level (the largest reduction of quantum noise reported so far), and (iii) show that balanced pumping of the two upper laser levels would achieve correlation of the laser phase noise with no locking at all. The resulting reduction in the phase noise of the beat note allows interferometric measurements of vastly enhanced sensitivity.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 1995
- DOI:
- 10.1103/PhysRevLett.74.4639
- Bibcode:
- 1995PhRvL..74.4639S