Forward-looking: The US space agency will soon send a new, experimental laser communication technology into space that is expected to show potential data transmission rates that are 10 to 100 times the speed of current state-of-the-art radio systems. The device is installed aboard the Psyche spacecraft, which is scheduled to launch no earlier than October 5, 2023.
You don't have to use magnetism or electrical charge to store data. It can be done using light, or more rather, the reflection of it. Okay, if you want to be really specific, it's done using the interference of infrared and visible electromagnetic waves, but let's not worry too much about that!