Daniel Loss, Paul Goldbart, and Alexander V. Balatsky, of the Department of Physics at the University of Illinois at Urbana-Champaign, publish in 1990 "Berry's Phase and Persistent Charge and Spin Currents in Textured Mesoscopic Rings", the first work formally connecting Michael Berry's Berry phase (1984) with the phenomenon of persistent currents described by Büttiker, Imry, and Landauer in 1983. The authors consider a mesoscopic conducting ring immersed in a static but non-uniform magnetic field — a magnetic texture that changes direction along the ring. The Zeeman interaction between the electron's spin and that texture couples orbital and spin motion, and forces the spin to rotate adiabatically, accumulating a Berry phase according to the exact geometry of the field traversed. They show that this geometric phase alone sustains persistent charge and spin currents in the system's ground state, even when the net magnetic flux through the ring is exactly zero: the Berry phase acts as an effective topological gauge flux, replacing the real magnetic field as the mechanism for breaking time-reversal symmetry. The result introduces the concept of a pure persistent spin current — spin-up electrons circulating in one direction and spin-down electrons in the opposite direction — and for the first time translates the Berry phase, until then considered mostly a geometric curiosity of the wave function, into a prediction of measurable electric current and magnetization in the laboratory. The work lays the conceptual groundwork for what would later develop into geometric and topological spintronics.