High-speed laser writing method could pack 500 terabytes of data into CD-sized glass disc

https://www.osa.org/en-us/about/newsroom/news_releases/2021/high-speed_laser_writing_method_could_pack_500_ter/

Lasers pack glass disc with permanent data... Discrete flaws are created in glass via laser. Each flaw has 2 different optical properties. Each flaw has 3 spatial coordinates. So each flaw has 2^5 states = 32 normal bits. Can write at 230 kilobytes  (100+ pages of text) per second. "...physical mechanism we use is generic,"

But, read speed needs improvement.