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Physics & astronomy professor Steven White and his grad student Simeng Yan have made the June 3 cover of Science with an illustration of their complex and groundbreaking work identifying the true ground state of a quantum spin liquid. Physicists have worked for more than 20 years to make such an identification. The UCI researchers did it using a well-known Japanese basket pattern called a kagome lattice, combined with algorithmic work first done by White, who carved out a large new field in quantum physics in 2003. The magazine cover depicts three possible phases of the kagome Heisenberg antiferromagnet, a model of geometrically “frustrated” magnetism: the diamond-pattern valence bond crystal (lower left), honeycomb valence bond crystal (lower right) and quantum spin liquid (empty upper wedge). Deviations of bond strengths from their average values are indicated by bond widths and colors (red being stronger, blue weaker). The researchers’ simulations show that the true ground-state phase is the quantum spin liquid.