Tag

Quantum Criticality

All articles tagged with #quantum criticality

Quantum-Critical Surprise: New Topological State Found in CeRu4Sn6
science1 month ago

Quantum-Critical Surprise: New Topological State Found in CeRu4Sn6

Researchers observed a novel topological semimetal state in CeRu4Sn6 at ultracold temperatures, a phase once deemed impossible, arising from quantum criticality that ties strong electron interactions to topology. The state was signaled by an unusual Hall effect without a magnetic field, indicating robust topological behavior with potential quantum-tech applications. The team plans to explore this state in other materials and refine the topology details. Published in Nature Physics.

Emergent Topology Arises in Quantum-Critical CeRu4Sn6
physics1 month ago

Emergent Topology Arises in Quantum-Critical CeRu4Sn6

Researchers at TU Wien report that the quantum material CeRu4Sn6 enters a quantum-critical regime at ultra-low temperatures where electrons lose their particle-like character, yet the system hosts an emergent topological semimetal state. They observed a spontaneous (anomalous) Hall effect without an external magnetic field, linking quantum fluctuations to topology and suggesting that topological properties can arise even when the conventional particle-picture fails. The work also points to a generalized, emergent view of topology and proposes focusing on quantum-critical materials to discover new topological phases.

"Novel 2D Van der Waals Metal Traps Heavy Electrons"
science2 years ago

"Novel 2D Van der Waals Metal Traps Heavy Electrons"

Researchers have discovered a two-dimensional heavy fermion system in the van der Waals metal CeSiI, which exhibits intriguing quantum criticality and superconductivity. This finding opens up new possibilities for studying the behavior of heavy fermions in two dimensions and exploring the potential applications of van der Waals materials in superconducting technologies. The data supporting the study are available in the paper and its Extended Data, with additional data accessible from the corresponding authors upon request.

Controlling Heavy Fermions with Moiré Kondo Lattice Gates.
physics3 years ago

Controlling Heavy Fermions with Moiré Kondo Lattice Gates.

Researchers have realized a synthetic Kondo lattice in AB-stacked MoTe2/WSe2 moiré bilayers, in which the MoTe2 layer is tuned to a Mott insulating state, supporting a triangular moiré lattice of local moments, and the WSe2 layer is doped with itinerant conduction carriers. They observed heavy fermions with a large Fermi surface below the Kondo temperature and demonstrated widely and continuously gate-tunable Kondo temperatures through either the itinerant carrier density or the Kondo interaction. This study opens the possibility of in situ access to the phase diagram of the Kondo lattice with exotic quantum criticalities in a single device based on semiconductor moiré materials.