1. Department of Physics &2. Astronomy, Texas Tech University, Lubbock, TX, USA;3. Nano Tech Center, Texas Tech University, Lubbock, TX, USA;4. Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX, USA
Abstract:
We report large amplitude modulation waveforms as large as ~ 10 V using vanadium dioxide micro-channel devices operating under current-controlled conditions. The self-sustained electrical oscillations were generated by controlling the applied current in the negative differential resistance region of the investigated devices. An appropriate value of internal capacitance was achieved as parasitic capacitance in the device structure to stabilize the electrical oscillations. This eliminates the need of an external pulsed source or any external passive component connected to the micro-channel devices. Amplitude and frequency of the oscillation were tuned by illuminating the device micro-channel with an external laser. An equivalent circuit model was developed to simulate the waveforms. A good agreement between experiment and simulation was verified.