Intermittency of dynamical phases in a quantum spin glass

Understand

Answering the question of existence of efficient quantum algorithms for NP-hard problems require deep theoretical understanding of the properties of the low-energy eigenstates and long-time coherent dynamics in quantum spin glasses.

• We discovered and described analytically the property of asymptotic orthogonality resulting in a new type of structure in quantum spin glass.
• Its eigen-spectrum is split into the alternating sequence of bands formed by quantum states of two distinct types ($x$ and $z$).
• Those of $z$-type are non-ergodic extended eigenstates (NEE) in the basis of $\{\sigma_z\}$ operators that inherit the structure of the classical spin glass with exponentially long decay times of Edwards Anderson order parameter at any finite value of transverse field $B_{\perp}$.