Morning Overview

New study finds quantum particles that live in just 1 dimension

Physicists have produced experimental evidence that anyons, exotic quasiparticles long thought to exist only in two-dimensional systems, can emerge in strictly one-dimensional quantum platforms. The results challenge a decades-old assumption about where fractional exchange statistics can appear and open a fresh line of inquiry for quantum computing hardware. Two independent research efforts, one using ultracold atoms in an optical lattice and another using a bosonic quantum gas with a mobile impurity, have now demonstrated that particles confined to a single spatial dimension can behave as neither fermions nor bosons.

Fermions, Bosons, and the Third Option

The standard model of particle physics sorts all elementary particles into two families. Fermions, which include electrons, protons, neutrons, and quarks, are the building blocks of matter and obey the Pauli exclusion principle, meaning no two can occupy the same quantum state. Bosons, by contrast, carry forces between matter particles and can pile into identical states without restriction. Every known particle slots neatly into one camp or the other, and the rules governing their behavior when swapped, known as exchange statistics, have been treated as settled physics for nearly a century, as summarized in educational overviews of matter and force particles.

Since the 1970s, theorists have predicted a third class of particle that sits somewhere between those two extremes. Dubbed “anyons,” these quasiparticles were expected to display fractional exchange statistics, picking up a quantum phase that is neither zero (like a boson) nor pi (like a fermion) when two of them trade places. The catch was dimensional: anyons were theorized to live exclusively in two-dimensional systems, because the topology of a flat plane allows particle paths to braid around each other in ways that three-dimensional space does not. Experimental confirmation of two-dimensional anyons arrived in 2020 in carefully engineered quantum Hall platforms, but one dimension remained largely unexplored, with most textbooks asserting that the mathematics simply did not permit fractional statistics on a line.

How Two Labs Broke the 2D Barrier

A peer-reviewed study published in Science described how researchers created Abelian anyons in one dimension by trapping ultracold atoms in an optical lattice and engineering a density-dependent Peierls phase. That technique allowed the team to tune the statistical phase of the quasiparticles continuously between bosonic and fermionic limits, effectively dialing how “anyon-like” the excitations became. The experiment observed distinctive quantum-walk signatures that matched theoretical predictions for one-dimensional anyons with arbitrary statistical phase, according to the indexed record of the study, which details how correlations and interference patterns deviate from those expected for ordinary bosons or fermions. NIST-affiliated physicist Alexey Gorshkov is listed among the contributors, tying the work to federal research infrastructure and long-running efforts to use optical lattices as analog quantum simulators.

A separate effort led by physicists at the University of Innsbruck took a different route. Rather than engineering a lattice phase, the Innsbruck group injected a mobile impurity into a one-dimensional ultracold bosonic gas and accelerated it, then analyzed the resulting momentum distribution of the combined object. The data showed emergent anyonic behavior, with the impurity and its surrounding cloud acting collectively as a new kind of quasiparticle that carries a tunable statistical phase. The underlying paper, published in Nature with DOI 10.1038/s41586-025-09016-9, was accompanied by a detailed theoretical companion on anyonization of bosons that maps measured observables onto an effective anyonic description and clarifies how the impurity-bath coupling encodes fractional statistics. Together, the two experiments attack the same question from opposite experimental angles, one by sculpting artificial gauge fields, the other by dressing a defect with correlations, and arrive at compatible conclusions that 1D anyons are physically realizable.

Why One Dimension Was Supposed to Be Off-Limits

The textbook argument against one-dimensional anyons rests on topology. In two dimensions, swapping two particles traces a path that cannot be smoothly shrunk to a point, giving the exchange a nontrivial phase that can take arbitrary values and is captured by the braid group. In one dimension, particles on a line can only pass through each other, and the standard braid group that governs 2D exchange statistics collapses to a simple permutation group with no room for intermediate phases. A theoretical paper posted to arXiv proposed an alternative algebraic structure called the “traid group,” which introduces hard-core three-body constraints that restore nontrivial exchange behavior even in 1D. The associated lattice model, termed the traid-anyon-Hubbard model, predicts intermediate statistics that sit between fermionic and bosonic limits, offering a formal escape route from the old dimensional restriction by encoding effective braiding into multi-particle collisions rather than literal over and under exchanges.

Complementary theoretical work has proposed a “swap model” for achieving anyonic correlations in 1D by exploiting the internal spin degrees of freedom of a spinor quantum gas. That framework, described in a preprint on bosonic anyonization, uses spin-charge separation and tilt potentials in strongly interacting gases to generate the same fractional statistics without requiring a two-dimensional substrate or explicit braiding paths. In this picture, effective exchanges occur when spins are swapped while particles remain ordered on the line, allowing the system to mimic anyonic phases through internal-state dynamics. The convergence of multiple independent theory papers with two separate experimental demonstrations suggests that 1D anyons are not a fluke of one particular platform but a general feature of low-dimensional quantum matter once interactions and internal structure are taken seriously.

Broader Evidence for 1D Quantum Strangeness

The anyon results land in a period of rapid progress across one-dimensional quantum physics. A peer-reviewed experiment in Nature Physics demonstrated a finite-energy phase transition in a one-dimensional trapped-ion quantum simulator with long-range interactions, proving that genuine 1D platforms can support collective phenomena once thought impossible outside higher dimensions. A related access portal via Springer Nature authentication underscores the growing interest in such systems among condensed-matter and quantum-information researchers who need institutional access to the detailed data and analysis. Stanford physicists separately discovered a new state of matter in a one-dimensional quantum gas by adding magnetic interactions to an ultracold system, expanding the catalog of exotic phases available in linear geometries and reinforcing the idea that 1D is no longer a theoretical backwater but a frontier for emergent behavior.

Material-science labs have also joined the push to exploit one-dimensionality, fabricating nanowires, atomic chains, and edge channels where electrons are forced to move along effectively single-file tracks. In such settings, strong correlations and restricted motion can produce charge fractionalization, spin-charge separation, and other hallmarks of Luttinger-liquid behavior that blur the line between particles and collective excitations. The new anyon experiments slot neatly into this landscape by showing that even exchange statistics, once considered a rigid, binary property, can become emergent and tunable in 1D. For quantum technologies, that means linear architectures such as ion strings, Rydberg chains, and superconducting resonator arrays may eventually host topologically inspired qubits that borrow robustness from anyonic phases without requiring fully two-dimensional hardware.

More from Morning Overview

*This article was researched with the help of AI, with human editors creating the final content.