Double-dimension serial reaction task in which color and alphabet were set as background and operating stimulus respectively was used to explore implicit learning in the present study. Subjects were instructed to react to the alphabets with or without the background colors in one of the following conditions: random sequence, regular sequence or blank (i.e., no background color).The results showed that random background color sequence interfered with the implicit learning of alphabet sequence. Participants' implicit learning score in the random background color sequence was significantly lower than those in the regular background color sequence and no color background conditions. Moreover, when compared with no-background-color condition, regular-background-color sequence did not affect the learning of alphabet sequence. Finally, it was found that background color could be implicitly processed regardless whether it was in regular or random sequence.

Facing the demand for applications such as wide-area terrain mapping and space-based atmospheric measurements, there is an urgent need to develop miniaturized single-photon detection systems with low power consumption that can be adapted to airborne platforms. Superconducting nanowire single-photon detectors (SNSPDs) have been applied to quantum information, bioimaging, deep space communication and long-range lidar with the advantages of high quantum efficiency, low dark count rate and fast detection rate. However, traditional SNSPD usually operate at 2.1 K or even lower, and the required cryogenic systems are large in size and weight, which are not easy to be applied to airborne platforms. Up to now, there is no international report on SNSPD applied to airborne platforms. How to apply SNSPD to airborne platforms is an urgent problem to be solved. In this paper, we designed and prepared a SNSPD with an operating temperature of 4.2 K. The superconducting detector chip is a four-channel photon number resolvable device with a photosensitive area of 60 μm×60 μm, which is coupled to a 200 μm diameter fiber by a beam compression system with a quantum efficiency of 50% @1064 nm at a temperature of 4.2 K. Finally, the time characteristics of a single channel were tested in response to different photon numbers. The timing jitter of four-photon response is the smallest, and the half-height width is 110 ps. This work not only supports airborne applications, but also has positive implications for promoting the development of general-purpose miniaturized SNSPD systems and their applications.