Sensing single proteins with diamonds Nuclear magnetic resonance is a powerful technique for medical imaging and the structural analysis of materials, but usually associated large-volume samples. Lovchinsky et al. exploited properties spin defect in diamond manipulated it quantum-logic protocol. They demonstrated detection spectroscopy multiple nuclear species within individual ubiquitin attached to specially treated surface at room temperature. Science , this issue p. 836

The negatively charged nitrogen-vacancy (NV-) center in diamond has realized new frontiers quantum technology. Here, the center's optical and spin resonances are observed under hydrostatic pressures up to 60 GPa. Our observations motivate powerful techniques measure pressure image high magnetic electric phenomena. further reveal a fundamental inadequacy of current model provide insight into its electronic structure.

Precise timekeeping is critical to metrology, forming the basis by which standards of time, length, and fundamental constants are determined. Stable clocks particularly valuable in spectroscopy because they define ultimate frequency precision that can be reached. In quantum qubit coherence time defines clock stability, from spectral linewidth We demonstrate a sensing protocol goes beyond sensor limited stability classical clock. Using this technique, we observed estimation scaling T as T-3/2...

Emitters of indistinguishable single photons are crucial for the growing field quantum technologies. To realize scalability and increase complexity optics technologies, multiple independent yet identical single-photon emitters required. However, typical solid-state sources inherently dissimilar, necessitating use electrical feedback or optical cavities to improve spectral overlap between distinct emitters. Here we demonstrate bright silicon vacancy (SiV−) centres in low-strain bulk diamond,...

Nuclear magnetic resonance spectroscopy and imaging at the ultimate sensitivity limit of single molecules or nuclear spins requires fundamentally new detection strategies. The strong coupling regime, when interaction between sensor sample dominates all other interactions, is one such strategy. In this classically forbidden completely unpolarized nuclei allowed, going beyond statistical fluctuations in magnetization. Here we realize an atomic (nitrogen–vacancy) to perform on four 29Si spins....

Nanometer-sized diamonds containing nitrogen-vacancy defect centers (NV) are promising nanosensors in biological environments due to their biocompatibility, bright fluorescence, and high magnetic sensitivity at ambient conditions. Here we report on the detection of ferritin molecules using noise induced by inner paramagnetic iron as a contrast mechanism. We observe significant reduction both coherence relaxation time presence surface nanodiamonds. Our theoretical model is excellent agreement...

We report on the noise spectrum experienced by few nanometer deep nitrogen-vacancy centers in diamond as a function of depth, surface coating, magnetic field and temperature. Analysis reveals double-Lorentzian spectra consistent with electronic spin bath, slower dynamics due to spin-spin interactions faster related phononic coupling. These results shed new light mechanisms responsible for affecting shallow spins at semiconductor interfaces, suggests possible directions further studies....

We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. use Hartmann-Hahn double resonance to coherently enhance signal from spin while decoupling noisy spin-bath, which otherwise limits sensitivity. As proof-of-principle we: (I) observe coherent oscillations between NV center weakly coupled spin, (II) demonstrate bath cooling prolongs coherence time sensor more than factor five. Our results provide route...

The negatively-charged silicon-vacancy (SiV$^-$) center in diamond is a promising single photon source for quantum communications and information processing. However, the center's implementation such technologies hindered by contention surrounding its fundamental properties. Here we present optical polarization measurements of centers bulk that resolve this state establish has $\langle111\rangle$ aligned split-vacancy structure with $D_{3d}$ symmetry. Furthermore, identify an additional...

The loss of coherence is one the main obstacles for implementation quantum information processing. efficiency dynamical decoupling schemes, which have been introduced to address this problem, limited itself by fluctuations in driving fields will themselves introduce noise. We challenge introducing concept concatenated continuous decoupling, can overcome not only external magnetic noise but also due fields. show theoretically that approach achieve relaxation times, and demonstrate...

We present the experimental demonstration of what are to our knowledge first two-dimensional planar plasmonic lenses formed by an array spatially varying cross-shaped apertures in a metallic film for Fresnel-region focusing. The design utilizes localized surface plasmon resonances occurring inside apertures, accompanied aperture geometry dependent phase shift, achieve desired spatial modulation transmitted field. performance with different configurations was evaluated using confocal scanning...

A quantitative understanding of the dynamics biological neural networks is fundamental to gaining insight into information processing in brain. While techniques exist measure spatial or temporal properties these networks, it remains a significant challenge resolve with subcellular resolution. In this work we consider fundamentally new form wide-field imaging for neuronal based on nanoscale magnetic field sensing optically active spins diamond substrate. We analyse sensitivity system...

We experimentally demonstrate the protection of a room-temperature hybrid spin register against environmental decoherence by performing repeated quantum error correction whilst maintaining sensitivity to signal fields. use long-lived nuclear correct multiple phase errors on sensitive electron in diamond and realize magnetic field sensing beyond time scales set natural decoherence. The universal extension time, robust noise at any frequency, demonstrates definitive advantage entangled...

Spins of negatively charged nitrogen-vacancy (NV${}^{\ensuremath{-}}$) defects in diamond are among the most promising candidates for solid-state qubits. The fabrication quantum devices containing these spin-carrying requires position-controlled introduction NV${}^{\ensuremath{-}}$ having excellent properties such as spectral stability, a long spin coherence time, and stable negative charge state. Nitrogen ion implantation annealing enable positioning qubits with high precision, but to date,...

Magnetic field fluctuations arising from fundamental spins are ubiquitous in nanoscale biology, and a rich source of information about the processes that generate them. However, ability to detect few involved without averaging over large ensembles has remained elusive. Here, we demonstrate detection gadolinium spin labels an artificial cell membrane under ambient conditions using single-spin nanodiamond sensor. Changes relaxation time sensor located lipid bilayer were optically detected...

Nanomechanical sensors and quantum nanosensors are two rapidly developing technologies that have diverse interdisciplinary applications in biological chemical analysis microscopy. For example, nanomechanical based upon nanoelectromechanical systems (NEMS) demonstrated chip-scale mass spectrometry capable of detecting single macromolecules, such as proteins. Quantum electron spins negatively-charged nitrogen-vacancy (NV) centers diamond modes nanometrology, including molecule magnetic...

A versatile biopolymer platform for advancing nanodiamonds (NDs) as unique magnetooptic materials biomedical applications is presented here. Precision coatings are designed by chemical reprogramming the functionalities of serum albumin via a straightforward synthesis protocol. Such biopolymers offer high biocompatibility and precise modification with various functional entities due to large number available reactive amino acid residues. Premodification these provides convenient approach...

Among promising color centers for single-photon sources in diamond, the negatively charged silicon-vacancy (SiV−) has 70% of its emission to zero-phonon line (ZPL), contrast nitrogen vacancy (NV−), which a broad spectrum. Fabricating single useful defect complexes with high yield and excellent grown-in properties by ion implantation proven be challenging. We have fabricated bright SiV− 60-keV focused beam subsequent annealing at 1000 °C positioning accuracy 15%.

Stimulated emission is the process fundamental to laser operation, thereby producing coherent photon output. Despite negatively charged nitrogen-vacancy (NV−) centres being discussed as a potential medium since 1980s, there have been no definitive observations of stimulated from ensembles NV− date. Here we show both theoretical and experimental evidence for using light in phonon sidebands around 700 nm. Furthermore, transition photoionization stimulating wavelength reduced 620 While lasing...

Magnetic resonance detection is one of the most important tools used in life-sciences today. However, as technique detects magnetization large ensembles spins it fundamentally limited spatial resolution to mesoscopic scales. Here we detect natural fluctuations nanoscale spin at ambient temperatures by measuring decoherence rate a single quantum response introduced extrinsic target spins. In our experiments 45 nm nanodiamonds with nitrogen–vacancy (NV) were immersed solution containing 5/2...

Efficient polarization of organic molecules is extraordinary relevance when performing nuclear magnetic resonance (NMR) and imaging. Commercially available routes to dynamical (DNP) work at extremely low-temperatures, thus bringing the out their ambient thermal conditions relying on solidification samples. In this we investigate transfer from optically-pumped nitrogen vacancy centers in diamond external room temperature. This described by both an extensive analytical analysis numerical...

A solid understanding of the implantation process N and Si ions into diamond is needed for controlled creation shallow color centers quantum computing, simulation, sensing applications. Here, molecular dynamics simulations simulated at 100--5000 eV kinetic energies different angles incidence. We find that ion channeling an important effect with onset energy depending on crystal orientation. Consequently, produce improved predictions as compared to standard Monte Carlo simulations. When...

We show a marked reduction in the emission from nitrogen-vacancy (NV) color centers single crystal diamond due to exposure of hydrogen plasmas ranging 700{\deg}C 1000{\deg}C. Significant fluorescence was observed beneath exposed surface at least 80mm depth after ~10 minutes, and did not recover post-annealing vacuum for seven hours 1100{\deg}C. attribute formation NVH by plasma induced diffusion hydrogen. These results have important implications quantum applications, inform our...

The strong-driving regime occurs when a quantum two-level system is driven with an external field whose amplitude greater than or equal to the energy splitting between system's states and typically identified breaking of rotating wave approximation (RWA). We report experimental study in which spin single nitrogen-vacancy (NV) center diamond strongly microwave fields arbitrary polarization. measure NV dynamics beyond RWA characterize limitations this technique for generating high-fidelity...