Very light particles with CP-violating couplings to ordinary matter, such as axions or axionlike particles, can mediate long-range forces between polarized and unpolarized fermions. We describe a new experimental search for such forces between unpolarized nucleons in two 250 kg Pb weights and polarized neutrons and electrons in a 3 He-K comagnetometer located about 15 cm away. We place improved constraints on the products of scalar and pseudoscalar coupling constants, g n p g N s < 4.2 × 10 −30 and g e p g N s < 1.7 × 10 −30 (95% C.L.) for axionlike particle masses less than 10 −6 eV, which represents an order of magnitude improvement over the best previous neutron laboratory limit.

No abstract

The realization of scalable systems for quantum information processing and networking is of utmost importance to the quantum information community. However, building such systems is difficult because of challenges in achieving all the necessary functionalities on a unified platform while maintaining stringent performance requirements of the individual elements. A promising approach that addresses this challenge is based on the consolidation of experimental and theoretical capabilities in quantum physics and integrated photonics. Integrated quantum photonic devices allow efficient control and read-out of quantum information while being scalable and cost effective. Here, the authors review recent developments in solid-state single photon emitters coupled with various integrated photonic structures, which form a critical component of future scalable quantum devices. Their work contributes to the further development and realization of quantum networking protocols and quantum logic on a scalable and fabrication-friendly platform.

No abstract