Figure 2: Cumulative density of states.
From: Quantum annealing for the number-partitioning problem using a tunable spin glass of ions
(a) For six ions and at trap frequency ωz=2π × 770 kHz, we plot the number of states (divided by the total Hilbert space dimension) below the normalized energy treshold (0: ground state energy, 1: energy of highest state), for different detunings from the centre-of-mass mode, δ=ωN−ωL. The density of states at low energies is seen to strongly increase when the detuning is slightly above a phonon resonance. In b the position of the resonances (measured from the centre-of-mass mode at δN=0) are shown.
