Heisenberg-Type Quantum Steering by Continuous Weak Measurement in Circuit QED *

Zhong Wang

Fig. 3 (Color online) Steering parameter $S_{mnl}^{yzx}$ versus measurement time $t$ and LO phse difference $\Delta\varphi$, in which $\varphi_m$, $\varphi_n$ change from 0 to $\pi/2$ and $\varphi_l=\pi/2$. The black line is the bound between keeping and violating inequality.