Coherent Photonic Transmission

Thomas P. Pearsall

Xiangyang Yu, Jianhong Li, Xiao-bin Li

Starting from the semiclassical theory of light–matter interaction, we have theoretically investigated the substantial influences of two coherent driving fields on manipulating the single-photon transmission probability in the extensively studied atom-cavity-waveguide coupled system. The results strictly demonstrate that under the relatively large photon-cavity detuning and moderately strong driving fields, the single-photon transmission probability increases remarkably from the original 0 to 1 by controlling the coherent fields in the nondissipative environment, which manifests the manipulation of the coherent fields as a sort of highly controllable external tool to efficiently act as an experimentally available all-optical quantum switching. In contrast, the behavior independent from variation of coherent fields and characterized by the stationary transmission spectrum appears under the photon-atom on-resonance condition. Similar properties can also be observed in the dissipative environment. These distinct characteristics essentially reveal some significant functionalities of coherent field control in influencing the single-photon transmission spectrum, which may have potential applications in designing efficient photonic devices.

Philip Rübeling, Jan Heine, Robert Johanning +1 more

Fiber-optical networks are well established to accommodate global data traffic via coherent information transmission. The next generation of telecommunications will require the integration of quantum information into fiber-optic networks, e.g., for quantum key distribution. A promising and scalable route to enable quantum networking is encoding quantum information into the frequency of photons. While the cointegration of frequency-entangled photons with coherent information transmission is achieved via spectral multiplexing, more resource-efficient approaches are required. In this work, we introduce and experimentally demonstrate a transceiver concept that enables the transmission of coherent and frequency-entangled photons over a single-frequency channel. Our concept leverages the serrodyne technique via electro-optic phase modulation leading to very different dynamics for entangled and coherent photons. This enables temporal multiplexing of the respective signals. We demonstrate the preservation of entanglement over the channel in the presence of coherent light. Our approach reveals a strong potential for efficient bandwidth use in hybrid networks.

Thomas P. Pearsall

Wei Hu, Xiao-San Ma, Bing Wang +2 more

Abstract We theoretically investigate the influences of two coherent driving fields on the asymmetric transmission of single photon in the atom-waveguide system. The atom is considered as a Λ system. One transition of the atom chirally couples to the waveguide. The other transition is driven by two coherent driving fields. The transmission probabilities for the single photon incidents from the left ( T lr ) and right ( T rl ) are given respectively. The calculated results show that one can realize T lr = 0 ( T rl ≠ 0) or T rl = 0 ( T lr ≠ 0) by manipulating the phase difference between the two coherent driving fields. The influence of the decay rate of the metastable state on the asymmetric transmission is also discussed.

Thomas P. Pearsall