Improvement of an Atomic Clock using Squeezed Vacuum.

  title={Improvement of an Atomic Clock using Squeezed Vacuum.},
  author={Ilka Kruse and Karsten Lange and Jan Peise and Bernd L{\"u}cke and Luca Pezz{\'e} and Jan J Arlt and Wolfgang Ertmer and Ch. Lisdat and Luis Esteves dos Santos and Augusto Smerzi and Carsten Klempt},
  journal={Physical review letters},
  volume={117 14},
Since the pioneering work of Ramsey, atom interferometers are employed for precision metrology, in particular to measure time and to realize the second. In a classical interferometer, an ensemble of atoms is prepared in one of the two input states, whereas the second one is left empty. In this case, the vacuum noise restricts the precision of the interferometer to the standard quantum limit (SQL). Here, we propose and experimentally demonstrate a novel clock configuration that surpasses the SQL… CONTINUE READING