Physicists find evidence of new state of matter in a simple oxide: "Shigeki Onoda, a theorist at the RIKEN Advanced Science Institute in Wako, recognized that experimentalists at The University of Tokyo had possibly discovered a new state of matter, called a ‘chiral spin liquid’ when they reported evidence of time-reversal symmetry breaking1—a difference between the trajectory of a particle moving along one path or its inverse—in the oxide called Pr2Ir2O7. If a material is magnetic, or in a magnetic field, its electrons will not obey time reversal symmetry; but in Pr2Ir2O7, neither contribution was present to explain what the experimentalists had observed.
Now, Onoda and colleague Yoichi Tanaka have explained how a chiral spin liquid could emerge from so-called ‘quantum spin fluctuations’—the motion of spins that occurs even at absolute zero2. “The possibility of a chiral spin liquid was first proposed twenty years ago and many physicists had lost hope to find it,” explains Onoda. “This is a revival of a phase that was found in a totally different system than where it was first expected.”"