Figure 3: Experimental values for the LG function are compared with bounds from quantum mechanics and macrorealist theories.
From: Violation of a Leggett–Garg inequality with ideal non-invasive measurements
(a) The populations of the four system-ancilla (nucleus–electron) states are manipulated with microwave and radio-frequency radiation. The experimentally determined value of the Leggett–Garg function at a static field of B=3.357 T is plotted (b) at 2.6 K for a thermal initial state and (c) at 2.7 K with a hyperpolarized initial state. The minimum bound for each macrorealist approach is also plotted: blue for moderate, red for adversarial. Error bars represent uncertainty in measurement of the final state, and the grey point and error bars are the result of correcting for known measurement errors (namely the population damping effects of the tomography pulse sequence).
