In addition to a bulk energy gap, topological insulators accommodate a conducting, linearly dispersed Dirac surface state. This state is predicted to become massive if time reversal symmetry is broken ...

Research into quantum criticality in Dirac fermion systems has rapidly evolved over recent years, enhancing our understanding of phase transitions driven by quantum fluctuations at zero temperature.

Urbana, IL -- Fundamental research in condensed matter physics has driven tremendous advances in modern electronic capabilities. Transistors, optical fiber, LEDs, magnetic storage media, plasma ...

UNIVERSITY PARK, Pa. — For the first time, scientists have observed a collection of particles, also known as a quasiparticle, that's massless when moving one direction but has mass in the other ...

Scientists have observed a unique particle that moves easily one way, yet resists at 90 degrees. These semi-Dirac fermions were observed using their energy signature in a topological metal. Particles ...

For the first time, scientists have caught a glimpse of a strange and elusive creature in the world of quantum physics—a semi-Dirac fermion. This unusual quasiparticle behaves as if it has no mass in ...

Materials whose gapless surface states are protected by crystal symmetries include mirror topological crystalline insulators and nonsymmorphic hourglass insulators. There exists only a very limited ...

“We weren’t even looking for a semi-Dirac fermion when we started working with this material, but we were seeing signatures we didn’t understand – and it turns out we had made the first observation of ...

An international team of scientists has discovered an exotic new form of topological state in a large class of 3D semi-metallic crystals called Dirac semimetals. The researchers developed extensive ...