MIT physicists have linked the surprising coexistence of superconductivity and magnetism to the behavior of “anyons,” exotic quasiparticles formed from splintered electrons. Their new theory, published in the Proceedings of the National Academy of Sciences, proposes these anyons can flow without friction under certain conditions. This could introduce a novel form of superconductivity and potentially enable the design of more stable qubits.
Conflicting Quantum States: Coexistence of Superconductivity & Magnetism
The surprising coexistence of superconductivity and magnetism was recently observed in materials like rhombohedral graphene and molybdenium ditelluride (MoTe2). For decades, these quantum states were considered mutually exclusive, as magnetism typically destroys superconductivity. However, experiments revealed this wasn’t always the case, prompting physicists to seek an explanation for how both states could emerge simultaneously within the same material. This discovery challenged long-held assumptions about the relationship between these fundamental quantum phenomena.
The theoretical work at MIT suggests that “anyons” – quasiparticles formed when electrons splinter into fractions – could be responsible for this unexpected coexistence. Specifically, the team found that anyons with a 2/3 electron charge encourage collective movement and superconductivity, overcoming the typical frustration that hinders their motion. These anyons emerge under specific conditions in two-dimensional materials like MoTe2, where electrons fractionalize without an external magnetic field, creating a pathway for this novel form of superconductivity.
The potential implications extend to quantum computing. If confirmed and controlled, superconducting anyons could provide a new way to design stable qubits – the fundamental building blocks of quantum computers. Unlike conventional bits, qubits leverage quantum mechanical properties to process information far more efficiently. This research offers a potential pathway toward realizing this technology, suggesting that the dream of powerful quantum computation may be one step closer to reality.
Anyon Quasiparticles Emerge in Two-Dimensional Materials
Anyons, exotic quasiparticles, emerge under specific conditions in two-dimensional materials like molybdenium ditelluride (MoTe2). These particles are created when electrons fractionalize, a phenomenon observed in MoTe2 without the need for an external magnetic field. Notably, the fractional quantum anomalous Hall effect (FQAH) within MoTe2 directly leads to the formation of these anyons, differing from the behavior of bosons and fermions which comprise most matter.
The type of anyon formed impacts its behavior; anyons with a 1/3 electron charge tend to resist collective movement, resulting in typical metallic conduction. However, the research indicates that anyons carrying 2/3 of an electron’s charge actively encourage collective motion. This particular fraction allows these typically sluggish particles to move together, potentially creating a superconducting state—a flow of current without resistance—similar to how electrons pair in conventional superconductors.
These findings suggest a pathway to a new form of superconductivity, one that could coexist with magnetism. Researchers applied quantum field theory to model the conditions where superconducting anyons could emerge, focusing on MoTe2’s FQAH. If confirmed and controlled, these superconducting anyons could revolutionize quantum computing by providing a novel way to design stable qubits—the fundamental building blocks of quantum computers.
“If our anyon-based explanation is what is happening in MoTe 2 , it opens the door to the study of a new kind of quantum matter which may be called ‘anyonic quantum matter,’” Todadri says.
Senthil Todadri
MoTe2 Modeling Reveals 2/3 Flavor Anyon Superconductivity
The MIT team modeled conditions within molybdenium ditelluride (MoTe2) to explore the emergence of superconducting anyons. Building on the observation of the fractional quantum anomalous Hall effect (FQAH) in MoTe2, they investigated how electrons fractionalize and what types of anyons are produced with increasing electron density. Their work focused on the interactions of anyons carrying either 1/3 or 2/3 of an electron’s charge, applying quantum field theory to understand collective behavior.
Researchers found that anyons with a 1/3 electron charge predictably resisted collective movement, leading to standard metallic conduction. However, the key finding revealed that anyons carrying 2/3 of an electron’s charge actively encourage collective motion. This particular fractional charge allows these typically sluggish particles to move together, potentially creating a superconducting state—a flow of current without resistance—similar to how electrons pair in conventional superconductors.
This theoretical work suggests a pathway for superconductivity to coexist with magnetism, utilizing the FQAH phenomenon within MoTe2. By modeling the conditions in which electrons fractionalize, the team identified that a predominance of 2/3-charge anyons could overcome typical frustration, enabling collective movement and potentially resulting in a superconducting state driven by these exotic quasiparticles rather than conventional electrons.
Fractional Quantum Anomalous Hall Effect & Anyon Formation
The fractional quantum anomalous Hall effect (FQAH) in materials like molybdenium ditelluride (MoTe2) directly leads to the formation of anyons—quasiparticles created when electrons fractionalize. Notably, this fractionalization occurs without an external magnetic field, a key characteristic of the process within MoTe2. These anyons represent a third type of particle, distinct from bosons and fermions, and exist specifically within two-dimensional spaces, offering a unique pathway to explore quantum phenomena.
Researchers found that the type of anyon formed dramatically impacts its behavior. Anyons carrying 1/3 of an electron’s charge tend to resist collective movement, resulting in typical metallic conduction. However, anyons with 2/3 of an electron’s charge actively encourage collective motion, potentially enabling a superconducting state—a flow of current without resistance. This particular fraction allows these normally sluggish particles to move together, similar to electron pairing in conventional superconductors.
The theoretical work focused on MoTe2 because it exhibits both superconductivity and the FQAH under specific conditions. Scientists modeled how electrons fractionalize within MoTe2, predicting the types of anyons produced as electron density increases. The research suggests that a dominance of 2/3 charge anyons could overcome the typical frustration that prevents anyon movement, potentially leading to a novel form of superconductivity involving these exotic quasiparticles.
