Laser frequency combs are light sources that produce evenly spaced, sharp lines across the spectrum, resembling the teeth of a comb. They serve as precise rulers for measuring time and frequency, and have become essential tools in applications such as lidar, high-speed optical communications, and space navigation. Traditional frequency combs rely on large, lab-based lasers. However, recent advancements have led to the development of chip-scale soliton microcombs, which generate ultrashort pulses of light within microresonators.

In conventional heat-assisted magnetic recording (HAMR), a laser is used to locally heat the recording medium to facilitate data writing. However, the thermal energy applied is largely dissipated within the medium and does not contribute directly to the recording efficiency. Moreover, this high-temperature process consumes substantial energy and raises concerns regarding the magnetic and physical degradation of the medium, especially under repeated use.

A research team from the Department of Energy’s Oak Ridge National Laboratory, in collaboration with North Carolina State University, has developed a simulation capable of predicting how tens of thousands of electrons move in materials in real time, or natural time rather than compute time.

Ferromagnetic semiconductors (FMSs) combine the unique properties of semiconductors and magnetism, making them ideal candidates for developing spintronic devices that integrate both semiconductor and magnetic functionalities. However, one of the key challenges in FMSs has been achieving high Curie temperatures (TC) that enable their stable operation at room temperature.