On the dream list of many condensed matter physicists is observing fractionalization, the phenomena of a collective state of electrons carrying a charge that is a fraction of the electron charge, without a magnetic field.

“This is not to say the electron itself can be split into pieces,” said Eun-Ah Kim, professor of physics in the College of Arts and Sciences (A&S). “Rather, a group of electrons can act like it carries a deficit of charge that is only a fraction of an electron charge. Such an observation is a pinnacle of non-trivial effect strong interaction among electrons can manifest.”

Achieving these states carrying a fractional charge is not only of intellectual interest, Kim said; it can be useful for new technological applications such as quantum computing.

Researchers in the Kim Group predict a way to achieve fractionalization without a magnetic field, a theory they detail in “Fractionalization in Fractional Correlated Insulating States at n ± 1/3 Filled Twisted Bilayer Graphene,” published in Physical Review Letters Sept. 8. Dan Mao, a Bethe/Wilkins/Kavli Institute at Cornell (KIC) postdoctoral fellow in the Laboratory of Atomic and Solid State Physics (LASSP), is lead author. Kim and doctoral student Kevin Zhang are co-authors.

Read the full story on the College of Arts and Sciences website.