Unveiling a Revolutionary Class of Particles: A Bold Leap for Quantum Mechanics

Within the numerous enigmas of quantum physics, subatomic entities do not always adhere to the principles of the classical world. They can occupy two locations simultaneously, penetrate solid barriers, and communicate instantaneously over large distances. These actions might appear impossible, but within the realm of quantum, researchers are investigating a variety of characteristics once deemed unattainable.

In a recent investigation, physicists at Brown University have identified a new kind of quantum particles referred to as fractional excitons, exhibiting unanticipated behaviors and potentially broadening the scientific community’s grasp of the quantum domain.

“Our conclusions suggest a completely new category of quantum particles that carry no net charge yet adhere to distinct quantum statistics,” stated Jia Li, a physics associate professor at Brown.

“The most thrilling aspect is that this revelation opens up a multitude of new quantum phases of matter, paving the way for future inquiries, enhancing our comprehension of fundamental physics, and perhaps offering innovative opportunities in quantum computing.”

Alongside Li, the research involved three graduate students—Naiyuan Zhang, Ron Nguyen, and Navketan Batra—and Dima Feldman, a physics professor at Brown. Zhang, Nguyen, and Batra share the title of co-first authors of the paper, which was released in Nature on Wednesday, Jan. 8.

The discovery made by the team revolves around a phenomenon known as the fractional quantum Hall effect, which is derived from the classical Hall effect, occurring when a magnetic field is applied to a conducting material to induce a lateral voltage.

The quantum Hall effect, observed at exceptionally low temperatures and elevated magnetic fields, demonstrates that this lateral voltage increases in distinct, separate increments. In the fractional quantum Hall effect, these increments occur in smaller, fractional amounts—equaling a fraction of an electron’s charge.

During their investigations, the scientists constructed a system comprising two thin sheets of graphene, a two-dimensional nanomaterial, divided by an insulating crystal of hexagonal boron nitride. This arrangement permitted them to meticulously regulate the movement of electric charges, along with enabling the creation of excitons, which arise from pairing an electron with an absence of an electron, termed a hole.

The team then subjected the system to extraordinarily strong magnetic fields, millions of times more intense than Earth’s. This allowed them to identify the unique fractional excitons, which displayed an unusual variety of behaviors.

Fundamental particles are generally classified into two groups. Bosons are particles that can occupy the same quantum state simultaneously, allowing numerous instances of them to coexist without limits. Conversely, fermions adhere to the Pauli exclusion principle, which states that no two fermions can share the same quantum state.

The fractional excitons detected in this study, however, did not conveniently fit into either classification. While they exhibited the fractional charges anticipated in the study, their actions reflected characteristics of both bosons and fermions, functioning almost as a blend of the two. This made them more akin to anyons, a particle category located between fermions and bosons—albeit the fractional excitons exhibited exceptional properties that distinguished them from anyons, as well.

“This surprising behavior indicates that fractional excitons might embody a wholly new category of particles with distinct quantum properties,” Zhang remarked. “We demonstrate that excitons can thrive in the fractional quantum Hall landscape and that some of these excitons stem from the pairing of fractionally charged particles, creating fractional excitons that do not behave like bosons.”

The acknowledgment of a new type of particles could eventually enhance methods for storing and manipulating information at the quantum level, leading to quicker and more dependable quantum computers, the team highlighted.

“We have effectively unlocked a new avenue for analyzing and controlling this phenomenon, and we are just beginning to explore its depths,” Li stated. “This marks the initial demonstration that these types of particles exist experimentally, and we are now investigating what may unfold from them.”

Future endeavors for the team will focus on examining how these fractional excitons interact and determining if their behavior can be manipulated.

“It feels as though we are right at the control panel of quantum mechanics,” Feldman remarked. “It’s an aspect of quantum mechanics that was previously unknown to us or, at the very least, not appreciated until now.”

This webpage was generated programmatically. To view the article in its original online position, please visit the link below:
https://phys.org/news/2025-01-discovery-class-particles-quantum-mechanics.html
Should you wish to remove this article from our website, kindly reach out to us