E-Mail IMAGE: Comparison between conventional HDD write head and newly proposed flux control HDD write head. In the flux control HDD write head, the magnetization of the FC device is reversed against... view more Credit: Hirofumi Suto WASHINGTON, March 9, 2021 -- Researchers at Toshiba Corporation in Japan have studied the operation of a small device fabricated in the write gap of a hard disk drive's write head to extend its recording density. The device, developed by HWY Technologies, is based on a design concept known as microwave-assisted magnetic recording, or MAMR. This technology, reported in the Journal of Applied Physics, by AIP Publishing, uses a microwave field generator known as a spin-torque oscillator. The spin-torque oscillator emits a microwave field causing the magnetic particles of the recording medium to wobble the way a spinning top does. This makes them much easier to flip over when the write head applies a recording magnetic field in the writing process.