Tunability of output frequency in heterogeneous spin torque nano oscillator by generated Oersted field.

The current induced magnetization precession dynamics by Spin Transfer Torque [STT] in a Spin Torque Nano Oscillator [STNO] device is investigated numerically by solving the Landau Lifshitz Gilbert Slonczewski [LLGS] equation. In the present study, we have devised a Heterogeneous based STNO device made of Ferro Magnetic [FM] Alloy. The base layer is made of Fe85B13Ni2 and the apex layer is made of Co2Fe0.4Mn0.6Si. The copper acts as a Non-Magnetic [NM] spacer. We have introduced the Current Induced Oersted Field [CIOF] and it is generated when the spin polarized current passes through the device. By varying the generated Oersted Field [OF] strength (Hoe) from 0 kA/m to 50 kA/m, as an increment of 10 kA/m the frequency tunability is achieved. The result imputes that, if we increase the OF strength from 0 kA/m to 50 kA/m frequency keeps on increasing, but the Power reduces. At 0 kA/m (in the absence of the OF), 26.36 GHz frequency with 6.116 (nW/mA2/GHz) is obtained. On the other hand, at 50 kA/m (in the presence of the OF), 115.9 GHz frequency with 2.105 (nW/mA2/GHz) is obtained. The author insinuates that the results are applicable for nanoscale spintronic devices in Extremely High-Frequency applications. [ABSTRACT FROM AUTHOR]