New State of Matter Found In Two-Dimensional Material
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New evidence suggesting the existence of a mysterious state of matter, known as quantum spin liquid, has been found by researchers in real material. The state, which was first predicted nearly four decades ago, causes the usually indivisible electrons to break into pieces.
Physicists from the University of Cambridge measured Majorana fermions, first signatures of the fractional particles, in a two dimensional material that had a structure akin to graphene. The findings of the study matched those of the Kitaev model, which is considered to be one of the main models for quantum spin liquid. The results were reported in the Nature Materials. "This is a new quantum state of matter, which has been predicted but hasn't been seen before," said Dr Johannes Knolle, co-author of the paper, "This is a new addition to a short list of known quantum states of matter".
Quantum spin liquid has not affirmatively been witnessed in nature, and therefore it is considered a mysterious state of matter that is presumed to hide in certain magnetic materials. Therefore, the evidence of electron splitting or fractionalization, which can occur only with the existence of quantum spill liquid, is a breakthrough discovery that presupposes the presence of the matter.
Normally, electrons act like tiny bar magnets in a usual magnetic material, and when the material is cooled down to low temperatures, they order themselves so that the north magnetic poles point towards the same direction. However, when a material contains a spin liquid state, no amount of cooling will align the bar magnets to point to a certain direction. Rather, it becomes a hotchpotch due to quantum fluctuations.
Until now, the pattern formation of Majorana fermions in quantum spin liquid had been a mystery, in spite of existing theoretical predictions. However, the recent experiments provide a direct evidence between quantum spin liquid and electron fractionalization in a two dimensional material. Majorana fermions can be exceedingly helpful in building quantum computers that would be not only be remarkably faster than conventional models of computers, but also conduct hitherto unachievable calculations.