Quantum mechanics

Theoretical physics

Eigenvalues and eigenvectors

Telecommunications

Computer science

Acoustics

Lattice (music)

Quantum system

Physics

Quantum

Sawtooth wave

Quantum state

Physical review. B./Physical review. B

We show that a quantum scar state, an atypical eigenstate breaking eigenstate thermalization hypothesis embedded in a many-body energy spectrum, can be constructed in flat band systems. The key idea of our construction is to make use of orthogonal compact localized states. We concretely discuss our construction scheme, taking a sawtooth flat lattice system as an example, and numerically demonstrate the presence of a quantum scar state. Examples of higher-dimensional systems are also addressed. Our construction method of quantum scar has broad applications to various flat band systems.

Flat band quantum scar