Concurrent light squeezing and spin squeezing in an atomic ensemble

Ezad Shojaee, Leigh Norris, Ben Q. Baragiola +4 more

Daniel Hemmer, Enrique Montaño, Ivan Deutsch +1 more

Shenchao Jin, Junlei Duan, Youwei Zhang +7 more

Squeezed spin states and squeezed light are both key resources for quantum metrology and quantum information science, but have been separately investigated in experiments so far. Simultaneous generation of these two types of quantum states in one experiment setup is intriguing but remains a challenging goal. Here, we propose a novel protocol based on judiciously engineered symmetric atom-light interaction, and report proof-of-principle experimental results of concurrent spin squeezing of 0.61±0.09 dB and light squeezing of 0.65_{-0.10}^{+0.11} dB in a hot atomic ensemble. The squeezing process is deterministic, yielding fixed squeezing directions for both the light field and the collective atomic spin. Furthermore, the squeezed light modes lie in the multiple frequency sidebands of a single spatial mode. This new type of dual squeezed state is applicable for quantum enhanced metrology and quantum networks. Our method can be extended to other quantum platforms such as optomechanics, cold atoms, and trapped ions.

Leigh Norris, Ben Q. Baragiola, Enrique Montaño +3 more

A. Kuzmich, Klaus Mølmer, Eugene Simon Polzik

We propose an experimentally feasible way to generate spin squeezing in an ensemble of V-type atoms. The proposal involves absorption of a squeezed light beam, and it does not require a large solid angle to be occupied by squeezed light. 50% of the amount of squeezing of the optical field can be transferred onto spin squeezing of the excited atomic states. The analogy with the input-output theory for quantum fields is used to elucidate this result. An experimental setup for generation and detection of spin squeezing within magnetic or hf manifolds is outlined.

Monika Schleier-Smith, Ian D. Leroux, Vladan Vuletić