We report the experimental realization of BOOMERANG (better observation of magnetization, enhanced resolution, and no gradient), a sensitive and general method of magnetic resonance. The prototype millimeter-scale NMR spectrometer shows signal and noise levels in agreement with the design principles. We present 1H and 19F NMR in both solid and liquid samples, including time-domain Fourier transform NMR spectroscopy, multiple-pulse echoes, and heteronuclear J spectroscopy. By measuring a 1H-19F J coupling, this last experiment accomplishes chemically specific spectroscopy with force-detected NMR. In BOOMERANG, an assembly of permanent magnets provides a homogeneous field throughout the sample, while a harmonically suspended part of the assembly, a detector, is mechanically driven by spin-dependent forces. By placing the sample in a homogeneous field, signal dephasing by diffusion in a field gradient is made negligible, enabling application to liquids, in contrast to other force-detection methods. The design appears readily scalable to μm-scale samples where it should have sensitivity advantages over inductive detection with microcoils and where it holds great promise for application of magnetic resonance in biology, chemistry, physics, and surface science. We briefly discuss extensions of the BOOMERANG method to the μm and nm scales.
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机译:我们报告了BOOMERANG的实验实现(更好地观察磁化强度,增强分辨率和无梯度),这是一种灵敏且通用的磁共振方法。原型毫米级NMR光谱仪显示的信号和噪声水平符合设计原则。我们在固体和液体样品中均提供了 1 sup> H和 19 sup> F NMR,包括时域傅里叶变换NMR光谱,多脉冲回波和异核J光谱。通过测量 1 sup> H- 19 sup> F J偶合,该最后一个实验完成了具有力检测NMR的化学特有光谱。在BOOMERANG中,永磁体组件在整个样本中提供均匀的磁场,而组件的谐波悬挂部分(即检测器)则由自旋相关力机械驱动。与其他力检测方法相比,通过将样品放置在均匀的磁场中,可以忽略由于磁场梯度扩散而引起的信号移相,从而可以应用于液体。该设计似乎易于扩展到微米级的样品,在这种情况下,它应具有比使用微线圈感应检测更高的灵敏度优势,并有望在生物,化学,物理和表面科学中应用磁共振。我们简要讨论了BOOMERANG方法对μm和nm尺度的扩展。
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