Robust single-parameter quantized charge pumping
  This paper investigates a scheme for quantized charge pumping based on single-parameter modulation. The device was realized in an AlGaAs-GaAs gated nanowire. We find a remarkable robustness of the quantized regime against variations in the driving signal, which increases with applied rf power. This feature together with its simple configuration makes this device a potential module for a scalable source of quantized current. 
B. Kaestner, V. Kashcheyevs, G. Hein, K. Pierz, U. Siegner, and H. W.   Schumacher