The demand to store ever-increasing volumes of information has resulted in the widespread implementation of data centers for Big Data. These centers consume massive amounts of energy (about 3% of global electricity supply) and rely on magnetization-based hard disk drives with limited storage capacity (up to 2 TB per disk) and lifespan (three to five years). Laser-enabled optical data storage is a promising and cost-effective alternative for meeting this unprecedented demand. However, the diffractive nature of light has limited the size to which bits can be scaled, and as a result, the storage capacity of optical disks.Researchers at USST, RMIT and NUS have now overcome this limitation by using earth-rich lanthanide-doped upconversion nanoparticles and graphene oxide flakes. This unique material platform enables low-power optical writing nanoscale information bits.A much-improved data density can be achieved for an estimated storage capacity of 700 TB on a 12-cm optical disk, comparable to a storage capacity of 28,000 Blu-ray disks. Furthermore, the technology uses inexpensive continuous-wave lasers, reducing operating costs compared to traditional optical writing techniques using expensive and bulky pulsed lasers.This technology also offers the potential for optical lithography of nanostructures in carbon-based chips under development for next-generation nanophotonic devices.