Tremendous research efforts have been dedicated into
the field
of photoresponsive nonvolatile memory devices owing to their advantages
of fast transmitting speed, low latency, and power-saving property
that are suitable for replacing current electrical-driven electronics.
However, the reported memory devices still rely on the assistance
of gate bias to program them, and a real fully photoswitchable transistor
memory is still rare. Herein, we report a phototransistor memory device
comprising polymer/perovskite quantum dot (QD) hybrid nanocomposites
as a photoresponsive floating gate. The perovskite QDs offer an effective
discreteness with an excellent photoresponse that are suitable for
photogate application. In addition, a series of ultraviolet (UV)-sensitive
insulating polymer hosts were designed to investigate the effect of
UV light on the memory behavior. We found that a fully photoswitchable
memory device was fulfilled by using the independent and sequential
photoexcitation between a UV-sensitive polymer host and a visible
light-sensitive QD photogates, which produced decent photoresponse,
memory switchability, and highly stable memory retention with a memory
ratio of 104 over 104 s. This study not only
unraveled the mystery in the fully photoswitchable functionality of
nonvolatile memory but also enlightened their potential in the next-generation
electronics for light-fidelity application.