Most optical memory storage methods developed in the past, including CDs and DVDs, are limited by the diffraction limit of light. A single data point cannot be smaller than the wavelength of the laser writing and reading the data. In the new work, the researchers proposed boosting the bit density of optical storage by embedding many rare-earth emitters within the material. By using slightly different wavelengths of light — an approach known as wavelength multiplexing — they hypothesized that these emitters could hold more data within the same area.

An interesting approach. In my limited understanding, this is comparable to getting more space by using different disc standards (CD, DVD, Bluray) at the same time.

That being said, on the consumer side everything seems to be moving towards solid state storage mediums. Even if this does get commercialized in the next ~5 years, I can’t see this competing with SSDs on the consumer side.