The exotic properties of quantum spin liquids (QSLs) have continually been of interest since Anderson’s 1973 ground-breaking idea. Geometrical frustration, quantum fluctuations, and low dimensionality are the most often evoked material’s characteristics that favor the long-range fluctuating spin state without freezing into an ordered magnet or a spin glass at low temperatures. Among the few known QSL candidates, organic crystals have the advantage of having rich chemistry capable of finely tuning their microscopic parameters. Here, we demonstrate the emergence of a QSL state in [EDT-TTF-CONH₂]₂⁺[BABCO−] (EDT-BCO), where the EDT molecules with spin-1/2 on a triangular lattice form layers which are separated by a sublattice of BCO molecular rotors. By several magnetic measurements, we show that the subtle random potential of frozen BCO Brownian rotors suppresses magnetic order down to the lowest temperatures. Our study identifies the relevance of disorder in the stabilization of QSLs.

自从安德森（Anderson）于1973年开创性构想以来，量子自旋液体（QSL）的奇异特性一直备受关注。几何挫折，量子涨落和低尺寸是最常引起人们注意的材料特性，这些特性有利于长期波动的自旋态，而不会在低温下冻结成有序的磁体或自旋玻璃。在少数已知的QSL候选物中，有机晶体的优势在于化学性质丰富，能够精细地调节其微观参数。在这里，我们演示了[EDT-TTF-CONH ₂ ] ₂ ⁺ [乙一种乙CØ-（EDT-BCO），其中在三角形晶格上具有spin-1 / 2的EDT分子形成被BCO分子转子的亚晶格隔开的层。通过几次磁测量，我们表明，冻结的BCO布朗转子的微妙的随机势将磁阶抑制到最低温度。我们的研究确定了QSL稳定过程中疾病的相关性。