This study proposes a spintronic based compact tunable nano-sized RF oscillator. The proposed design provides parametric performance improvement as compared with the designs already reported in literature. This design also offers higher operating frequency up to range of several GHz, which can be tuned by a DC bias current. The proposed magnetic tunnel junction-spin torque oscillators (MTJ-STO) model overcomes the limitation of low output power which is prime issue in spin torque oscillators (STOs). This is achieved by employing multi-stage amplifier with impedance matching stages. In addition to that, mutual phase locking mechanism of STOs is introduced to act as a remedy for broadening of the spectrum linewidth, which is a critical issue in traditional oscillators. The hybrid model presented in this study contains spin torque based MTJ, which is compatible with CMOS technology. The modelling of proposed circuit has been done in Verilog-A and simulation results have been verified using HSPICE.

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Design of magnetic tunnel junction-based tunable spin torque oscillator at nanoscale regime

References

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