Extra-low-frequency noise in giant magnetoresistance recording heads

An untralow-noise amplification system was used to analyze the extra-low-frequency (ELF) noise in giant magnetoresistance heads. It was determined that the ELF noise created by giant magnetoresistance heads are magnetic in origin and that it has a noise power spectral density of 1/f. After subjecting the giant magnetoresistance heads to moderate current testing, it was found that the two-level random telegraph noise (RTN) it creates is affected by the applied field, sense current, and temperature.