Inspired by the success of graphene, various two-dimensional (2D) non-hexagonal
graphene allotropes having sp 2-bonded tetragonal rings in free-standing (hypothetical) …

In recent years, 2D materials have been widely used in optical and photonic applications
such as mode lockers, optical switches, polarizers, and optical modulators. As is known …

The topological flat band (TFB) has been proposed theoretically in various lattice models, to
exhibit a rich spectrum of intriguing physical behaviors. However, the experimental …

Flat band systems are currently under intense investigation in quantum materials, optical
lattices, and metamaterials. These efforts are motivated by potential realization of strongly …

Bound states of two interacting particles moving on a lattice can exhibit remarkable features
that are not captured by the underlying single-particle picture. Inspired by this phenomenon …

Flat energy bands of model lattice Hamiltonians provide a key ingredient in designing
dispersionless wave excitations and have become a versatile platform to study various …

Recently there has been intense interest in kagome metals, which are expected to host flat
bands (FBs). However, the observed “FBs” are not flat over the whole two-dimensional …

The discovery of superconductivity in twisted bilayer graphene has triggered a resurgence of
interest in flat-band superconductivity. Here, we investigate the square-octagon lattice …

Line-graph (LG) lattices are known for having flat bands (FBs) from the destructive
interference of Bloch wave functions encoded in only lattice symmetry. Here, we develop a …

We report the appearance of multiple numbers of completely flat band states in an extended
Lieb lattice model in two dimensions with five atomic sites per unit cell. We also show that …