Fig. 1: Experimental realization of a non-Gaussian Stirling heat engine.
From: Tuning the performance of a micrometer-sized Stirling engine through reservoir engineering
a The big red spot represents the primary optical trap and the small red spots represent the secondary flashing optical trap at different time instances t1–t3. b, c The distance δa(t) from the primary trap at which the secondary trap was flashed as a function of t for engineering a Gaussian and a non-Gaussian reservoir, respectively. d The probability distribution of particle displacements, ρ(x), for the engineered Gaussian/thermal (solid blue circles) and the non-Gaussian reservoir with κ = 27 (red hollow squares) for a nearly identical Teff. e A quintessential Stirling cycle between a hot non-Gaussian (κ = 20) bath at \({T}_{{{{{{{{\rm{eff}}}}}}}}}^{{{{{{{{\rm{H}}}}}}}}}=1824\) K and a cold Gaussian reservoir with \({T}_{{{{{{{{\rm{eff}}}}}}}}}^{{{{{{{{\rm{C}}}}}}}}}=1570\) K. The trap stiffness k is varied linearly in the expansion/compression steps. Having a fixed primary trap and a second flashing optical trap, as opposed to just the latter, prevented the trapped particle from escaping the trap and allowed for long experiments. ρ(x) of the particle measured at the four-state points (at equilibrium) labeled ①–④ is also shown. The black lines are Gaussian fits.
