The propagation of decelerating Airy pulses in non-instantaneous cubic medium is investigated both theoretically and numerically. In a Debye model, at variance with the case of accelerating Airy and Gaussian pulses, a decelerating Airy pulse evolves into a single soliton for weak and general non-instantaneous response. Airy pulses can hence be used to control soliton generation by temporal shaping. The effect is critically dependent on the response time, and could be used as a way to measure the Debye type response function. For highly non-instantaneous response, we theoretically find a decelerating Airy pulse is still transformed into Airy wave packet with deceleration. The theoretical predictions are confirmed by numerical simulations.

Laser communication using photons should consider not only the transmission environment’s effects, but also the performance of the single-photon detector used and the photon number distribution. Photon communication based on the superconducting nanowire single-photon detector (SNSPD) is a new technology that addresses the current sensitivity limitations at the level of single photons in deep space communication. The communication’s bit error rate (BER) is limited by dark noise in the space environment and the photon number distribution with a traditional single-pixel SNSPD, which is unable to resolve the photon number distribution. In this work, an enhanced photon communication method was proposed based on the photon number resolving function of four-pixel array SNSPDs. A simulated picture transmission was carried out, and the error rate in this counting mode can be reduced by 2 orders of magnitude when compared with classical optical communication. However, in the communication mode using photon-enhanced counting, the four-pixel response amplitude for counting was found to restrain the communication rate, and this counting mode is extremely dependent on the incident light intensity through experiments, which limits the sensitivity and speed of the SNSPD array’s performance advantage. Therefore, a BER theoretical calculation model for laser communication was presented using the Bayesian estimation algorithm in order to analyze the selection of counting methods for information acquisition under different light intensities and to make better use of the SNSPD array’s high sensitivity and speed and thus to obtain a lower BER. The counting method and theoretical model proposed in this work refer to array SNSPDs in the deep space field.

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