The behavior of room temperature self-sustained current oscillations resulting from sequential resonance tunneling in a doped weakly-coupled GaAs/AlAs superlattice(SL)is investigated under hydrostatic pressure.From at...The behavior of room temperature self-sustained current oscillations resulting from sequential resonance tunneling in a doped weakly-coupled GaAs/AlAs superlattice(SL)is investigated under hydrostatic pressure.From atmosphere pressure to 6.5 kbar,oscillations exist in the whole plateau of the I-V curve and oscillating characteristics are affected by the pressure.When hydrostatic pressure is higher than 6.5 kbar,the current oscillations are completely suppressed although a current plateau still can be seen in the 1-V curve.The plateau disappears when the pressure is close to 13.5kbar.As the main effect of hydrostatic pressure is to lower the X point valley with respect to Г point valley,the disappearance of oscillation and the plateau shrinkage before Г-X resonance takes place are attributed to the increases of thermoionic emission and nonresonant tunneling components determined by the lowest Г-X barrier height in GaAs/AlAs SL structure.展开更多
Vertical transport I-V relations of type-I GaAs/A1As superlattices with doped wells and weak coupling between wells at 77K were investigated with quasistatic and dynamic method.Spontaneous current oscillations are als...Vertical transport I-V relations of type-I GaAs/A1As superlattices with doped wells and weak coupling between wells at 77K were investigated with quasistatic and dynamic method.Spontaneous current oscillations are also investigated.The domain formation time 70±30 ns is directly measured.By using discrete-tunneling model,the key parameters of the relation between tunneling current and the bias between adjacent wells were quantitatively determined from the experimental data.展开更多
基金Supported in part by the National Natural Science Foundation of China under Grant No.19574071.
文摘The behavior of room temperature self-sustained current oscillations resulting from sequential resonance tunneling in a doped weakly-coupled GaAs/AlAs superlattice(SL)is investigated under hydrostatic pressure.From atmosphere pressure to 6.5 kbar,oscillations exist in the whole plateau of the I-V curve and oscillating characteristics are affected by the pressure.When hydrostatic pressure is higher than 6.5 kbar,the current oscillations are completely suppressed although a current plateau still can be seen in the 1-V curve.The plateau disappears when the pressure is close to 13.5kbar.As the main effect of hydrostatic pressure is to lower the X point valley with respect to Г point valley,the disappearance of oscillation and the plateau shrinkage before Г-X resonance takes place are attributed to the increases of thermoionic emission and nonresonant tunneling components determined by the lowest Г-X barrier height in GaAs/AlAs SL structure.
基金Supported by the Fujian Natural Science Foundation under Grant No.A97009.
文摘Vertical transport I-V relations of type-I GaAs/A1As superlattices with doped wells and weak coupling between wells at 77K were investigated with quasistatic and dynamic method.Spontaneous current oscillations are also investigated.The domain formation time 70±30 ns is directly measured.By using discrete-tunneling model,the key parameters of the relation between tunneling current and the bias between adjacent wells were quantitatively determined from the experimental data.
