Spontaneous self-sustained chaotic current oscillations are observed experimentally in lightly-doped weakly-coupled GaAs/Al0.45Ga0.55As superlattices at room temperature for the first time.The mole fraction of Aluminu...Spontaneous self-sustained chaotic current oscillations are observed experimentally in lightly-doped weakly-coupled GaAs/Al0.45Ga0.55As superlattices at room temperature for the first time.The mole fraction of Aluminum in the barrier is chosen to be 0.45 to suppress the thermal carrier leakage through the X-band valley,The effective nonlinearity induced by the sequential well-to-well resonant tunneling can still be strong enough to induce spontaneous chaotic current oscillations even at room temperature,The frequency spectrum of the chaotic current oscillations is ranged from DC to 4 GHz,which can be used as ultra-wide-band noise sources with a bandwidth of several Giga Hertz.展开更多
基金supported by the Key Program of the National Natural Science Foundation of China (10834004)the Natural Science Fund of Jiangsu Province (BK2010005, BK2011362 and SBY201120087)China Postdoctoral Science Foundation Funded Project (2011M500953)
文摘Spontaneous self-sustained chaotic current oscillations are observed experimentally in lightly-doped weakly-coupled GaAs/Al0.45Ga0.55As superlattices at room temperature for the first time.The mole fraction of Aluminum in the barrier is chosen to be 0.45 to suppress the thermal carrier leakage through the X-band valley,The effective nonlinearity induced by the sequential well-to-well resonant tunneling can still be strong enough to induce spontaneous chaotic current oscillations even at room temperature,The frequency spectrum of the chaotic current oscillations is ranged from DC to 4 GHz,which can be used as ultra-wide-band noise sources with a bandwidth of several Giga Hertz.
