Magnetic Resonance Towards Single Nuclear Spin Sensitivity Based On Single Solid State Spin In Diamond

The precise detection and imaging of magnetic fields is an important topic in biology, material science, medicine, geology and physics. Magnetometry has been also developed these years in different aspects, such as material[1-3], biology[4-9] and physics[10-15]. The sensitivity, spatial resolution and stabilitiy of magnetometry has improved greatly through these developments. Direct observation of spin structures with atomic-scale resolution has been developed with spin polarized scanning tunneling microscopy (SP-STM) and magnetic exchange force microscopy (MExFM)[16]. Furthermore the detection of a single electronic spin[17]and ensemble of nuclear spins[18,19] has been realized through magnetic resonance force microscopy (MRFM). Another system SQUID, with better sensitivity but worse spatial resolution, has demonstrated scanning magnetometry[20,21]. To meet the request to improve sensitivity and spatial resolution simutaneously, a spin microscope system based on fluorescence of a single-atom excited center was proposed by Chernobrod and Berman[22]. As well as this, a review by Budker and Romalis[23], they studied quantum coherence and found it plays an important role in optical magetometry. Thus nitrogen vacancy (NV) center in diamond emerged as a state-of-art candidate for spin microscope system[22]. The NV center can be located precisely[26], has beneficial optical properties[26], and long coherence time[27].In this thesis, we have developed an NV magnetometry sensor and demonstrated nanoscale NMR with single nuclear spin sensitivity[25]. In chapter1, we introduce the basic physics and essential properties of NV center in diamond. Theoretical description of AC field sensing and electron/nuclear spin sensing by NV magnetometry is then summarized. And its applications in material, biology and physics is introduced. In chapter2, the multi-pass protocols is investigated to enhance sensitivity and it is demonstrated that the high-order dynamical decoupling pulse sequence can be implemented in magnetometry. And the pulse sequence is then optimized. In chapter3, a series of periodical dynamical decoupling pulse sequences in single and double transition are compared. The anomalous decoherence effect produced by13C nuclear spin ensemble in1.1%13C natural abundance high-purity diamond is observed. In chapter4, we study nuclear magnetic resonance spectroscopy in the strong coupling regime. The sensitivity is enhanced by square root of the number of nuclear spins compared by microscope statistical fluctuation. Nuclear magnetic resonance spectroscopy of four29Si nuclear spins is performed. We exploit the field gradient created by the diamond atomic sensor, in concert with compressed sensing, to realize imaging protocols, enabling individual nuclei to be located with angstrom precision. The achieved signal-to-noise ratio under ambient conditions allows single nuclear spin sensitivity to be achieved within seconds. In chapter5, we try to improve the spectral linewidth using correlation spectroscopy. The spectral linewidth is narrower compared with dynamical decoupling protocols. In chapter6, we sense and characterize the interactions between a single13C-13C nuclear spin dimer located about lnm from the NV center. From the measured interaction we derive the spatial configuration of the dimer with atomic-scale resolution. These results indicate that, in combination with advanced material-surface engineering, central spin decoherence under dynamical decoupling control may be a useful probe for nuclear magnetic resonance single-molecule structure analysis.