Figure 2
From: Ensemble of Thermostatically Controlled Loads: Statistical Physics Approach

Spectral analysis of the hard model. κ = 0.1, τ = 1, x − = −2, x ↓ = −1, x ↑ = 1, x + = 2. The axes are Re[λ n ] and Im[λ n ]. Red and blue lines mark isolines of the real and imaginary parts of det(M(λ)), respectively (see Supplementary Information (SI) for details). Any crossing of a blue line and a red line corresponds to an eigenvalue, λ n .