Figure 2
From: Higher-order spin and charge dynamics in a quantum dot-lead hybrid system

(a) Observed spin and charge signals (the singlet probability and the average of the sensor signal 〈V sensor 〉) as a function of the interaction time. Red circles show the spin signal (left axis). The blue trace shows the charge signal (right axis). The smooth lines are exponential fits resulting in the relaxation time of 3.0 μs for the spin, and 1.8 μs for the charge. (b) Statistics of the charge signal at the operation point. Histogram of observed values of the charge sensor V sensor (on the x axis), N(V sensor )/N tot is plotted as a function of the interaction time (y axis). The two peaks, at V sensor = −960 mV, and −780 mV, correspond to the (1,1) and the (0,1) charge states, respectively. The weight of the (0,1) component increases with the longer interaction time. (c) Schematic of the spin relaxation by a first-order tunneling process. An electron escapes from the QD, and the QD becomes empty. Another electron comes in after that.