Micromagnetic writing on 8 nm grains and readback with various readers have been studied. For a conventional writer recording a pseudorandom binary sequence with 2 Tb/in2 channel bit density, user densities of 1.52 and 1.09 Tb/in2 could be achieved with a rotated single sense head (RSH) and a normally oriented single head (NSH), respectively, using 2 nm sampling period, a minimum mean squared error equalizer, and a Viterbi detector. Simulation indicated that an RSH with multiple scans and 2-D equalization provided better resistance to a skew angle of 15° than an NSH. An optimized shingled writer was proposed; simulation indicated that an RSH and rotated head array could reach a user areal density of 3.76 and 4.52 Tb/in2 for two grains per channel bit, which was close to the predicted maximum user areal density (4.66 Tb/in2) for this grain size obtained with an ideal writer and reader.
- Magnetoresistive head
- micromagnetic writer
- two-dimensional magnetic recording (TDMR)