Response characteristics of trapping loss in acoustic chargetransport devices

A model of the response characteristics of trapping loss in acoustic charge transport (ACT) devices on GaAs is presented. Through the use of a computer simulation of the interactions of signal electrons with traps, the model can be used to predict the time or frequency domain responses of the device for arbitrary signal waveforms and various trap distributions. The analysis procedures are discussed in detail for two cases of interest in normal ACT operation, namely, the cases of periodic pulse and single-frequency sinusoidal input signals. For these cases, the predicted dependences of the pulse degradation and frequency response, respectively, on the trap characteristics are presented. The predicted responses are compared to experimental results and to predictions from a previous analytical model