Microwave-Free Nuclear Magnetic Resonance at Molecular Scales

Abstract

The implementation of nuclear magnetic resonance (NMR) at the nanoscale is a major challenge, as conventional systems require relatively large ensembles of spins and limit resolution to mesoscopic scales. New approaches based on quantum spin probes, such as the nitrogen-vacancy (NV) centre in diamond, have recently achieved nano-NMR under ambient conditions. However, the measurement protocols require application of complex microwave pulse sequences of high precision and relatively high power, placing limitations on the design and scalability of these techniques. Here we demonstrate a microwave-free method for nanoscale NMR using the NV centre, which is a far less invasive, and vastly simpler measurement protocol. By utilising a carefully tuned magnetic cross-relaxation interaction between a subsurface NV spin and an external, organic environment of proton spins, we demonstrate NMR spectroscopy of ${}^1$H within a $\approx (10\mathrm{nm}{)}^3$ sensing volume. We also theoretically and experimentally show that the sensitivity of our approach matches that of existing microwave control-based techniques using the NV centre. Removing the requirement for coherent manipulation of either the NV or the environmental spin quantum states represents a significant step towards the development of robust, non-invasive nanoscale NMR probes.

7 pages, 4 figures

References in corpus (10)

• High-sensitivity diamond magnetometer with nanoscale resolution
• Scanning magnetic field microscope with a diamond single-spin sensor
• Dynamic polarization of single nuclear spins by optical pumping of NV color centers in diamond at room temperature
• Broadband Magnetometry and Temperature Sensing with a Light Trapping Diamond Waveguide
• Nanoscale NMR Spectroscopy and Imaging of Multiple Nuclear Species
• Spectroscopy of Surface-Induced Noise Using Shallow Spins in Diamond
• Microwave-free magnetometry with nitrogen-vacancy centers in diamond
• Spurious harmonic response of multipulse quantum sensing sequences
• Wide-band, nanoscale magnetic resonance spectroscopy using quantum relaxation of a single spin in diamond
• Spin dynamics of diamond nitrogen-vacancy centres at the ground state level anti-crossing and all-optical low frequency magnetic field sensing

Cited by in corpus (14)

• Non-neurotoxic Nanodiamond Probes for Intraneuronal Temperature Mapping
• Spin properties of dense near-surface ensembles of nitrogen-vacancy centres in diamond
• Towards hyperpolarization of oil molecules via nitrogen-vacancy centers in diamond
• Microwave-free vector magnetometry with nitrogen-vacancy centers along a single axis in diamond
• Quantum probe hyperpolarisation of molecular nuclear spins
• Impact of surface functionalisation on the quantum coherence of nitrogen vacancy centres in nanodiamond
• Microwave-assisted cross-polarization of nuclear spin ensembles from optically-pumped nitrogen-vacancy centers in diamond
• Photoluminescence at the ground state level anticrossing of the nitrogen-vacancy center in diamond
• The non-vanishing effect of detuning errors in dynamical decoupling based quantum sensing experiments
• Two-electron-spin ratchets as a platform for microwave-free dynamic nuclear polarization of arbitrary material targets
• Influence of dynamical decoupling sequences with finite-width pulses on quantum sensing for AC magnetometry
• Quantum bath control with nuclear spin state selectivity via pulse-adjusted dynamical decoupling
• High precision single qubit tuning via thermo-magnetic field control
• Dynamical nuclear polarization for dissipation-induced entanglement in NV centers