发表机构
University of California, Berkeley; Lawrence Berkeley National Laboratory; University of Texas at Austin（加州大学伯克利分校; 劳伦斯伯克利国家实验室; 德克萨斯大学奥斯汀分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究报道了一种高密度并五苯共晶DHP/Pc，在室温下实现微秒级自旋相干和相干控制，通过分子堆积与三重态能量设计克服了密集自旋系统的相干损失，为系综量子传感提供了新途径。
AI 中文摘要
在固定体积内最大化可寻址自旋的数量可以提高系综量子传感器的灵敏度，但密集堆积通常会增强偶极相互作用和激发态输运，缩短相干时间并抑制光学读出。这里我们报道了一种6,13-二氢并五苯与并五苯的2:1共晶（DHP/Pc），其中含有33.3摩尔%的并五苯（$3.3\ imes10^{5}$ ppm；$9.51\ imes10^{20}$ cm$^{-3}$），其体积自旋位点密度比之前的基准——NV金刚石和并五苯掺杂的对三联苯（PDP）——高出两个数量级以上。尽管密度如此之高，DHP/Pc仍表现出微秒级的自旋相干性、室温光探测磁共振和相干控制。时间分辨测量表明，长寿命三重态布居主要通过系间窜越产生，并表现出强烈的非热子能级极化。密度泛函理论计算进一步表明，天然共晶几何结构削弱了相邻并五苯之间的电子耦合，而较高的DHP三重态能量则对三重态迁移形成了势垒。这些结果确定了分子堆积和共形成体三重态能量作为在高自旋位点密度系统中保持相干的互补设计参数，证明了共晶化是通往致密、光学可寻址自旋材料用于室温系综量子传感的一条有前景的途径。
英文摘要
Maximizing the number of addressable spins within a fixed volume can improve ensemble quantum sensor sensitivity, but dense packing usually increases dipolar interactions and excited-state transport, shortening coherence and suppressing optical readout. Here we report a 2:1 cocrystal of 6,13-dihydropentacene and pentacene (DHP/Pc) containing 33.3 mol% pentacene ($3.3\times10^{5}$ ppm; $9.51\times10^{20}$ cm$^{-3}$), a volumetric spin-site density more than two orders of magnitude above previous benchmarks, NV-diamond and pentacene-doped p-terphenyl (PDP). Despite this density, DHP/Pc exhibits microsecond spin coherence, room-temperature optically detected magnetic resonance and coherent control. Time-resolved measurements indicate that the long-lived triplet population is generated predominantly by intersystem crossing and exhibits strong, non-thermal sublevel polarization. Density-functional theory calculations further suggest that the native cocrystal geometry weakens electronic coupling between neighboring pentacenes, while the higher DHP triplet energy creates a barrier to triplet migration. These results identify molecular packing and coformer triplet energetics as complementary design parameters for preserving coherence in high spin-site density systems, demonstrating cocrystallization as a promising route to dense, optically addressable spin materials for room-temperature ensemble quantum sensing.
CommentsMain article and supplementary information, 30 Pages total, 4 Main figures, 17 Supplementary Figures
