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Amorphous carbon underlayers are found to control Co(001) orientation of Co73Cr18Pt6Ta3 magnetic recording layers.

A method of heat-assisted magnetic recording (HAMR) potentially suitable for probe-based storage systems is characterized. In this work, field emission current from a scanning tunneling microscope (STM) tip is used as the heating source. Pulse voltages of 2-7 V with a duration of 500 ns were applied to a CoNi/Pt multilayered film. Different types of Ir/Pt and W STM tips were used in the experiment. The results show that thermally recorded magnetic marks are formed with a nearly uniform mark size of 170 nm when the pulse voltage is above a threshold voltage. The threshold voltage depends on the material work function of the tip, with W having a threshold voltage about 1 V lower than Pt. The emission area of our tip-sample system derived from an analytic expression for field emission current is approximately equal to the mark size, and is largely independent of pulse voltage. This emission area is large compared to lateral heat diffusion in the film. Thus higher applied voltages lead to higher peak temperatures in the model of the write process, but the mark diameter remains relatively unchanged. Index Terms--Field emission, high-density recording, prolate spheroidal coordinates, scanning tunneling microscope.

We characterized a method of heat-assisted magnetic recording, which is potentially suitable for probe-based storage systems. The field emission current from a scanning tunneling microscope tip was used as the heating source. Various pulse voltages were applied to two types of CoNi/Pt multilayered films: one is strongly coupled with low coercivity, and the other is weakly coupled with high coercivity. Experimental results show that marks achieved in strongly coupled medium are larger than that in granular one. An external magnetic field was then applied to those marks. For weak fields (lower than the coercivity of the medium) the size of marks changes distinctly in the strongly coupled medium but not in the granular one. A model of magnetic domain dynamics is built to quantitatively explain the experimental results. It agrees with experiments. Based on this model, we will be able to figure out the proposals to achieve small marks for ultrahigh recording density. [ABSTRACT FROM AUTHOR]

A method of heat-assisted magnetic recording potentially suitable for probe-based storage systems is characterized. In this work, field-emission current from a scanning tunneling microscope tip is used as the heating source. Pulse voltages of 2–7 V were applied to a CoNi/Pt multilayered film. During heating, various external magnetic fields were applied. Experimental results show that a positive magnetic field increases mark size while a negative field decreases mark size, compared to the case of writing without an external field in which an average mark size of 170 nm was achieved. In addition, a positive field reduces the threshold voltage of writing as well. A synthesized model is built to quantitatively simulate the experimental results. It includes the model of emission current, heat transfer, and dynamics of magnetic domains in the film. Simulation results show that the calculated mark size in various cases is consistent with experimental results. Based on this model, we will be able to figure out the proposals to achieve small marks for the goal of 1 Tbit/in.2 recording density. [ABSTRACT FROM AUTHOR]

A method of heat-assisted magnetic recording, which is potentially suitable for probe-based storage systems, is characterized. Experimental results reveal that marks achieved in strongly coupled medium are larger than in granular one.

A method of heat-assisted magnetic recording (HAMR) potentially suitable for probe-based storage systems is characterized. In this work, field emission current from a scanning tunneling microscope (STM) tip is used as the heating source. Pulse voltages of 2-7 V with a duration of 500 as were applied to a CoNiIPt multilayered film. Different types of Ir/Pt and W STM tips were used in the experiment! The results show that thermally recorded magnetic marks are formed with a nearly uniform mark size of 170 nm when the pulse voltage is above a threshold voltage. The threshold voltage depends on the material work function of the tip, with W having a threshold voltage about 1 V lower than Pt. The emission area of our tipasample system derived from an analytic expression for field emission current is approximately equal to the mark size, and is largely independent of pulse voltage. This emission area is large compared to lateral heat diffusion in the film. Thus higher applied voltages lead to higher peak temperatures in the model of the write process, but the mark diameter remains relatively unchanged. [ABSTRACT FROM AUTHOR]