Best articles

(Browse our full list of articles here)

“Probing electric-dipole-enabled transitions in the excited state of the nitrogen-vacancy center in diamond”, T. Delord, R. Monge, G.I. Lopez-Morales, O. Bach, C.E. Dreyer, J. Flick, C.A. Meriles, submitted. Available as arXiv:2405.16280.

The excited orbitals of color centers typically show stronger electric dipoles, which can serve as a resource for entanglement, emission tuning, or electric field sensing. Here, we use resonant laser excitation to expose strong transition dipoles in the excited state (ES) orbitals of the negatively charged nitrogen vacancy center in diamond. By applying microwave electric fields, we perform strong Rabi driving between ES orbitals, and show that the dressed states can be tuned in frequency and are protected against fluctuations of the transverse electric field.

“Photoinduced charge injection from shallow point defects in diamond into water”, K. Xu, D. Pagliero, G.I. Lopez Morales, J. Flick, A. Wolcott, and Carlos A. Meriles, ACS Appl. Mater. Interfaces, in press.

Thanks to its low or negative surface electron affinity and chemical inertness, diamond is attracting broad attention as a source material of solvated electrons produced by optical excitation of the solid-liquid interface. Here we probe the photocurrent response of water surrounded by single-crystal diamond surfaces engineered to host shallow nitrogen-vacancy (NV) centers. We observe clear signatures of diamond-induced photocurrent throughout the visible range. Experiments as a function of laser power suggest that NV centers and other co-existing defects — likely surface traps — contribute to carrier injection, though we find that NVs dominate in the limit of high illumination intensities. These results open new perspectives in the application of diamond-liquid interfaces to photo-carrier-initiated chemical and spin processes in fluids.

“Correlated spectroscopy of electric noise with color center clusters”, T.  Delord, R. Monge, C.A. Meriles, Nano Lett. 24, 6474 (2024). Available online in open access form and also as arXiv:2401.07814.

By simultaneously co-monitoring the spectra of multiple NVs in sub-diffraction clusters, we show the ability to deterministically induce Stark shifts in the observed optical resonances, hence allowing us to identify electrostatically coupled sets of emitters. We build on these cross-correlated measurements to determine the relative three-dimensional positions of interacting NVs in a cluster as well as the location and charge sign of proximal traps. Our results can be generalized to other color centers and open intriguing opportunities for the manipulation of nanoscale spin-qubit clusters connected via electric fields.

“3D-mapping and manipulation of photocurrent in an optoelectronic diamond device”, A.A. Wood, D.J. McCloskey, N. Dontschuk, A. Lozovoi, R.M. Goldblatt, T. Delord, D.A. Broadway, J.-P. Tetienne, B. C. Johnson, K.T. Mitchell, C.T.-K. Lew, C.A. Meriles, A.M. Martin, submitted. Available as arXiv:2402.07091.

We combine charge-state sensitive optical microscopy and photoelectric detection of NV centers to directly image the flow of charge carriers inside a diamond optoelectronic device, in 3D and with temporal resolution. We optically control the charge state of background impurities inside the diamond on-demand, resulting in drastically different current flow such as filamentary channels nucleating from specific, defective regions of the device. We then optically engineered conducting channels that control carrier flow, key steps towards optically reconfigurable, wide bandgap designer optoelectronics.

“Photo-induced charge state dynamics of the neutral and negatively charged silicon vacancy centers in room-temperature diamond”, G. Garcia-Arellano, G.I. López-Morales, N.B. Manson, J. Flick, A.A. Wood, and C.A. Meriles, Adv. Sci. 112308814 (2024). Available online as open access article and as arXiV:2403.10941.
We use multi-color confocal microscopy and density functional theory to examine photo-induced SiV recombination ¾ from neutral, to single-, to double-negatively charged ¾ over a broad spectral window in chemical-vapor-deposition diamond under ambient conditions. For the SiV0 to SiV transition, we find a linear growth of the photo-recombination rate with laser power at all observed wavelengths, a hallmark of single photon dynamics. Laser excitation of SiV, on the other hand, yields only fractional recombination into SiV2, a finding we interpret in terms of a photo-activated electron tunneling process from proximal nitrogen atoms.

“Reversible optical data storage below the diffraction limit”, R. Monge, T. Delord, C.A. Meriles, Nat. Nanotech. 19, 202 (2024). Available as arXiV:2402.11312. See related presentation here.

Color centers in wide-bandgap semiconductors feature metastable charge states that can be interconverted with the help of optical excitation at select wavelengths. Here, we leverage strain-induced heterogeneity in the optical transitions of color centers in diamond to demonstrate selective charge state control of individual point defects sharing the same diffraction-limited volume. Further, we apply this approach to dense color center ensembles, and show rewritable, multiplexed data storage with large areal density. These results portend opportunities for alternative approaches to information processing in the form of devices with enhanced optical storage capacity.

“Resonant versus non-resonant spin readout of a nitrogen-vacancy center in diamond under cryogenic conditions”, R. Monge,*, T. Delord*, G. Thiering, A. Gali, C.A. Meriles, Phys. Rev. Lett. 131, 236901 (2023). Available as arXiv:2312.02907.

We examine the impact of spin-selective, narrow-band laser excitation on NV readout under cryogenic conditions. Specifically, we demonstrate up to a 4.5-fold improvement in sensitivity compared to that possible with non-resonant (green) illumination, largely due to a boost in readout contrast and integrated photon count. We also leverage nuclear spin relaxation under resonant excitation to polarize the 14N host, which we then prove beneficial for spin magnetometry.

“Room-temperature photo-chromism of silicon vacancy centers in CVD diamond”, A. Wood, A. Lozovoi, Z-H. Zhang, S. Sharma, G.I. López Morales, H. Jayakumar, N. de Leon, C.A. Meriles, Nano Lett. 23, 1017 (2023). Available as arXiv:2211.13141

We use confocal fluorescence microscopy to activate and probe charge interconversion between all three charge states of SiV (neutral, single- and double-negatively-charged) under ambient conditions. In particular, we witness the formation of SiV0 via a two-step capture process of diffusing, photo-generated holes. Further, we show that continuous red illumination induces the converse process, first transforming SiV0 into SiV, then into SiV2-. Our results shed light on the charge dynamics of SiV and promise opportunities for nanoscale sensing and quantum information processing.

“Quantum sensing via magnetic-noise-protected states in an electronic spin dyad”, C.A. Meriles, P.R. Zangara, D. Pagliero, Adv. Quant. Tech. 2300098 (2023). Available as arXiv:2306.17273.

We theoretically investigate the coherent spin dynamics of a hetero-spin system formed by a spin featuring a non-zero crystal field and in proximity to a paramagnetic spin-1/2 center . We identify pairs of levels separated by field-insensitive transition frequencies, and show that the zero-quantum coherences we create between them can be remarkably long-lived. Further, we find these coherences are selectively sensitive to ‘local’ — as opposed to ‘global’ — field fluctuations, suggesting these spin dyads could be exploited as a nanoscale gradiometer for precision nanoscale magnetometry or for magnetic-noise-free electrometry and thermal sensing.

“Spin dynamics of a solid-state qubit in proximity to a superconductor”, R. Monge, T. Delord, N. Proscia, Z. Shotan, H. Jayakumar, J. Henshaw, P. Zangara, A. Lozovoi, D. Pagliero, P.D. Esquinazi, T. An, I. Sodemann, V.M. Menon, C.A. Meriles, Nano Lett., 23, 422 (2023).  Available as arXiv:2207.07648. See related presentation here.

We use an all-diamond scanning probe to investigate the spin dynamics of a single nitrogen-vacancy (NV) center proximal to a high-critical-temperature superconducting film in the presence of a weak magnetic field. We find that the presence of the superconductor increases the NV spin coherence lifetime, a phenomenon we tentatively rationalize as a change in the electric noise due to a superconductor-induced redistribution of charge carriers near the NV site.

“Detection and modeling of carrier capture by single point defects under variable electric fields”, A. Lozovoi, Y. Chen, G. Vizkelethy, E. Bielejec, J. Flick, M. Doherty, C.A. Meriles, Nano Lett. 23, 4495 (2023)Available as arXiv:2306.01572. See related presentation here.

Using an externally gated potential to minimize space-charge effects, we measure the hole capture probability by an individual negatively charged NV. To interpret these observations, we run semi-classical Monte Carlo simulations modeling carrier trapping through a cascade process of phonon emission, and obtain electric-field-dependent capture probabilities in good agreement with experiment.

“Imaging dark charge emitters in diamond via carrier-to-photon conversion”, A. Lozovoi, G. Vizkelethy, E. Bielejec, C.A. Meriles, Sci. Adv. 8, eabl9402 (2022). Available as arXiv:2201.05237

We monitor the fluorescence from a negatively charged nitrogen-vacancy (NV) center in diamond as we illuminate its vicinity. Cyclic charge state conversion of neighboring point defects sensitive to the excitation beam leads to a position-dependent stream of photo-generated carriers whose capture by the probe NV leads to a fluorescence change. This “charge-to-photon” conversion scheme allows us to image other individual point defects surrounding the probe NV, including non-fluorescent “single-charge emitters” that would otherwise remain unnoticed.

“Microwave-free dynamic nuclear polarization via sudden thermal jumps”, C.A. Meriles, P.R. Zangara, Phys. Rev. Lett. 128, 037401 (2022). Available as arXiv:2201.09092. See related presentation here.

We investigate the dynamics of a system hosting a polarizing agent formed by two distinct paramagnetic centers near a level anti-crossing. We show that nuclear spins polarize efficiently under a cyclic protocol that combines alternating thermal jumps and radio-frequency pulses connecting hybrid states with opposite nuclear and electronic spin alignment with no need for microwave or optical excitation. Central to this process is the difference between the spin-lattice relaxation times of either electron spin species, transiently driving the electronic spin bath out of equilibrium after each thermal jump.

“Optical activation and detection of charge transport between individual colour centres in diamond”, A. Lozovoi, H. Jayakumar, D. Daw, G. Vizkelethy, E. Bielejec, J. Flick, M.W. Doherty, C.A. Meriles, Nat. Electron. 4, 717 (2021). Available as arXiv:2110.12272. See related presentation here.

In these experiments, a ‘source’ NV undergoes optically-driven cycles of ionization and recombination to produce a stream of photo-generated carriers, one of which we subsequently capture via a ‘target’ NV several micrometers away. Our observations suggest the formation of bound exciton states with large orbital radii, here enabled through the action of unscreened Coulomb potentials. These states manifest in the form of giant carrier capture cross-sections, orders of magnitude greater than anticipated. Besides their fundamental interest, our results open intriguing prospects in the use of free carriers as a quantum bus to mediate effective interactions between paramagnetic defects in a solid-state chip.

“Magnetic-field-induced delocalization in hybrid electron-nuclear spin ensembles”, D. Pagliero*, P.R. Zangara*, J. Henshaw, A. Ajoy, R.H. Acosta, N. Manson, J. Reimer, A. Pines, C.A. Meriles, Phys. Rev. B 103, 064310 (2021). Available as arXiv:2006.07736.

We use field-cycling-assisted dynamic nuclear polarization to demonstrate magnetic-field-dependent activation of nuclear spin transport from otherwise isolated strongly-hyperfine-coupled sites. With the help of a toy model comprising electron and nuclear spins, we recast our observations in terms of a dynamic phase diagram featuring zones of active or forbidden nuclear spin current separated by boundaries defined by the interplay between spin Zeeman, dipolar, and hyperfine couplings. These findings could prove relevant in applications to spin-based quantum information processing and nanoscale sensing.

“Probing metastable space-charge potentials in a wide bandgap semiconductor”, A. Lozovoi*, H. Jayakumar*, D. Daw, A. Lakra, C.A. Meriles, Phys. Rev. Lett. 125, 256602 (2020). Available as arXiv:2012.10810. 

Combining local optical excitation and fluorescent imaging , we induce and monitor the formation of space charge fields in diamond whose presence we extract from the shape of charge distributions in probe color centers. Further, with the help of previously crafted charge patterns, we unveil a rich interplay between local and extended sources of space charge field, which we then exploit to show space-charge-induced carrier guiding. Our work could prove relevant to the investigation of solar cell operation, in studies to probe the dynamics of magneto-resistance with sub-micron resolution, or in the realization of novel quantum technology concepts combining charge and spin,

“Optically pumped spin polarization as a probe of many-body thermalization”, D. Pagliero, P. Zangara, J. Henshaw, A. Ajoy, R.H. Acosta, J.A. Reimer, A. Pines, C.A. Meriles, Science Adv. 6, eaaz6986 (2020).  Available as arXiv:2005.00647

We investigate the spin diffusion dynamics of 13C in diamond, which we dynamically polarize at room temperature via optical spin pumping of engineered color centers. Unexpectedly, we find excellent thermal contact throughout the nuclear spin bath, regardless the hyperfine coupling strength, which we attribute to effective carbon-carbon interactions mediated by the electronic spin ensemble. In particular, we measure spin diffusion constants up to two orders of magnitude greater than that expected from homo-nuclear spin couplings. Our results open intriguing opportunities to study the onset of thermalization in a system by controlling the internal interactions within the bath.

“Long-term spin state storage using ancilla charge memories”, H. Jayakumar,  A. Lozovoi, D. Daw, C.A. Meriles, Phys. Rev. Lett., 125, 236601 (2020). Available as arXiv:2003.13148.

We introduce an alternative path to spin qubit detection comprising spin-to-charge conversion and long-term storage of the emitted carriers via ancillary charge traps. This strategy allows one to replace the numerous individual spin readouts — exceeding hundreds of thousands in a normal measurement — by a single collective inspection of the trap ensemble upon repeating the control protocol a pre-defined number of times. Our results pave the route toward enhanced forms of color-center-based metrology down to the limit of individual point defects, while opening intriguing opportunities for on-chip, carrier-based transport of information between distant spin qubits.

“Microcavity-coupled emitters in 2D hexagonal boron nitride”, N.V. Proscia, H. Jayakumar, X. Ge, G. Lopez-Morales, Z. Shotan, W. Zhou, C.A. Meriles, V.M. Menon, Nanophot. 9, 2937 (2020). Available as  arxiv:1906.06546.

We demonstrate “pick and place” integration of a Si3N4 microdisk optical resonator with a single-photon-emitter (SPE) host in the form of ~20-nm-thick hexagonal boron nitride (hBN). The film folds around the microdisk maximizing contact to ultimately form a composite hBN/Si3N4 structure. The local strain that develops in the hBN film at the resonator circumference deterministically activates a low density of SPEs within the whispering gallery mode volume of the microdisk. These conditions allow us to demonstrate cavity-mediated excitation and incipient coupling of hBN color centers to the microdisk cavity modes.

“Mechanical rotation via optical pumping of paramagnetic impurities”, P.R. Zangara, A. Wood, M.W. Doherty, C.A. Meriles, Phys. Rev. B 100, 235410 (2019). Available as arXiv:1912.03524.

We examine the dynamics of NV-P1 spin pairs under under continuous optical excitation , and theoretically show that cross-relaxation between the NV and P1 spins must induce rigid rotation of the diamond crystal. Further, we find that physical rotation introduces a distance-independent coupling between remote spin pairs, which can ultimately lead to entanglement between otherwise non-interacting NV-P1 pairs.

13C dynamic nuclear polarization in diamond via a microwave-free ‘integrated’ cross effect”, J. Henshaw, D. Pagliero, P.R. Zangara, B. Franzoni, A. Ajoy, R. Acosta, J.A. Reimer, A. Pines, C.A. Meriles, Proc. Natl. Acad. Sci. USA 116, 18334 (2019). Available as arXiv:1909.06642.

We demonstrate efficient microwave-free 13C DNP via consecutive magnetic field sweeps and continuous optical excitation. By comparing the 13C DNP response for different crystal orientations, we show that the process is robust to magnetic field/NV misalignment, a feature that makes the present technique suitable to diamond powders and settings where the field is heterogeneous. Applications to shallow NVs could capitalize on the greater physical proximity between surface paramagnetic defects and outer nuclei to efficiently polarize target samples in contact with the diamond crystal.

“Spin coherent quantum transport of electrons between defects in diamond”, L.M. Oberg, E. Huang, P.M. Reddy, A. Alkauskas, A.D. Greentree, J.H. Cole, N.B. Manson, C.A. Meriles, M.W. Doherty, Nanophot. 8, 1975 (2019). Available as arXiv:1905.07084.

While individual spin registers have been used to implement small-scale diamond quantum computing, the realization of a large-scale device requires the development of an on-chip quantum bus for transporting information between distant qubits. This paper introduces a method for coherent quantum transport of an electron and its spin state between distant NV centers. Transport is achieved by the implementation of spatial stimulated adiabatic Raman pas- sage through the optical control of the NV center charge states and the confined conduction states of a diamond nanostructure (credit, Doherty group, ANU).

“Two-electron-spin ratchets as a platform for microwave-free dynamic nuclear polarization of arbitrary material targets”, P.R. Zangara, J. Henshaw, D. Pagliero, A. Ajoy, J.A. Reimer, A. Pines, C.A. Meriles, Nano Lett. 19, 2389 (2019). (ASAP article). Available as arXiv:1904.08563v1

We study the case of an NV center in diamond interacting with a near-surface paramagnetic defect (P1), in turn coupled  to protons outside the diamond crystal. We theoretically show that protons spin-polarize efficiently upon a magnetic field sweep across the NV–P1 level anti-crossing. The polarization transfer process is robust to NV misalignment relative to the external magnetic field, and efficient over a broad range of electron-electron and electron-nuclear spin couplings, even if proxy spins feature short coherence or spin-lattice relaxation times.

“Dynamics of frequency-swept nuclear spin optical pumping in powdered diamond at low magnetic fields”, P.R. Zangara, S. Dhomkar, A. Ajoy, K. Liu, R. Nazarian, D. Pagliero, D. Suter, J.A. Reimer, A. Pines, C.A. Meriles, Proc. Natl. Acad. Sci. USA 116, 2512 (2019). Available as arXiv:1902.06805.

We articulate experiment, theory, and numerical modeling to shed light on the optical pumping of 13C spins in an NV-hosting diamond powder subjected to simultaneous laser excitation and MW frequency sweeps.  The understanding we gain should help expedite applications where powders are intrinsically advantageous, including the hyper-polarization of target fluids in contact with the diamond surface or the use of hyperpolarized particles as contrast agents for in-vivo imaging.

“Microwave-assisted cross-polarization of nuclear spin ensembles from optically-pumped nitrogen-vacancy centers in diamond”, F. Shagieva, S. Zaiser, P. Neumann, D.B.R. Dasari, R. Stöhr, A. Denisenko, R. Reuter, C.A. Meriles, J. Wrachtrup, Nano Lett. 18, 3731 (2018). (ASAP article). Available as arXiv:1803.05608v1.

Here we demonstrate variable-magnetic-field cross-polarization from the NV electronic spin to protons in a model viscous fluid in contact with the diamond surface. Our experiments suggest slower molecular diffusion at nm distances from the diamond surface compared to that in bulk, an observation consistent with present models of the microscopic structure of a fluid close to a solid interface.

“Charge dynamics in near-surface, variable-density ensembles of nitrogen-vacancy centers in diamond”, S. Dhomkar, H. Jayakumar, P.R. Zangara, C.A. Meriles, Nano Lett. 18, 4046 (2018). (ASAP article). Available as arXiv:1807.00229.

Using multi-color confocal microscopy, we show that near-surface NVs ionize and recombine via single-photon processes due to concentration-dependent state hybridization with orbitals from neighboring traps. Further, we observe charge transfer from and to NVs in the dark which we reproduce semi-quantitatively via Monte Carlo modeling. These findings can find application for nanoscale electro-chemical sensing, or for data storage with sub-diffraction resolution.

“Orientation independent room-temperature optical 13C hyperpolarization in powdered diamond”, A. Ajoy, K. Liu, R. Nazaryan, X. Lv, P.R. Zangara, B. Safvati, G. Wang, D. Arnold, G. Li, A. Lin, P. Raghavan, E. Druga, S. Dhomkar, D. Pagliero, J.A. Reimer, D. Suter, C.A. Meriles, A. Pines, Science Adv. 4, eaar5492 (2018). Available as arXiv:1806.09812 

Dynamic polarization of nuclear spins via optically pumped NVs is an intriguing route to enhanced-sensitivity NMR but applications have been limited to single crystals. Here we attain record levels of 13C spin polarization in powdered diamond under ambient conditions. These results pave the way towards the use of hyperpolarized diamond particles as imaging contrast agents for biosensing and, ultimately, for the hyperpolarization of nuclear spins in arbitrary liquids brought in contact with their surface.

“Multi-spin-assisted optical pumping of bulk 13C nuclear spin polarization in diamond”, D. Pagliero, K.R. Koteswara Rao, P.R. Zangara, S. Dhomkar, H.H. Wong, A. Abril, N. Aslam, A. Parker, J. King, C.E. Avalos, A. Ajoy, J. Wrachtrup, A. Pines, C.A. Meriles, Phys. Rev. B 97, 024422 (2018)(Editor’s choice). Also available as arXiv:1711.07576.

One of the most remarkable properties of the nitrogen-vacancy (NV) center in diamond is that optical illumination initializes its electronic spin almost completely, a feature that can be exploited to polarize other spin species in their proximity to record levels under ambient conditions. Here we show 13C spin pumping near 51 mT takes place via a multi-spin cross relaxation process involving the NV spin and the electronic and nuclear spins of neighboring P1 centers.

“On-demand generation of neutral and negatively-charged silicon-vacancy centers in diamond”, S. Dhomkar, P. Zangara, C.A. Meriles, Phys. Rev. Lett. 120, 117401 (2018). Available as arXiv:1803.06569v1.

The silicon-vacancy (SiV) center in diamond is emerging as a new platform for nano-photonics, information processing, and sensing but the controlled conversion between its most common charge states (negative and neutral) has so far proven elusive. Here we demonstrate on demand generation of SiV- and SiV0 over large areas using laser excitation of variable wavelength and intensity.

“Near-deterministic activation of single-photon emitters in hexagonal boron nitride”, N. Proscia, Z. Shotan, H. Jayakumar, P. Reddy, M. Dollar, A. Alkauskas, M.W. Doherty, C.A. Meriles, V.M. Menon, Optica 5, 1128 (2018).  Available as arXiv:1712.01352.

We demonstrate strain-induced activation of single-photon emitters in hexagonal boron nitride into a bright state through charge trapping in deformation potentials. The process is nearly 100% efficient yielding stable emitters at room temperature over arbitrarily shaped spatial patterns. This article was chosen for Optica’s cover

KikuchietalAn_ThumbnailFig“Long-distance excitation of nitrogen-vacancy centers in diamond via propagating surface spin waves”, D. Kikuchi, D. Prananto, K. Hayashi, A. Laraoui, N. Mizuochi, M. Hatano, E. Saitoh, Y. Kim, C.A. Meriles, T. An, Appl. Phys. Express 10, 103004 (2017). Also available as arXiv:1708.00596.

Coherent communication over mesoscale distances is a necessary condition for the application of solid-state spin qubits to scalable quantum information processing. As an initial step in this direction, here we make use of room-temperature spin waves to mediate the interaction between the microwave field from an antenna and the spin of an NV center 3.6 mm away.

Screen Shot 2017-03-25 at 5.43.24 PM“Non-volatile nuclear spin memory enables sensor-unlimited nanoscale spectroscopy of small spin clusters”, M. Pfender, N. Aslam, H. Sumiya, S. Onoda, P. Neumann, J. Isoya, C.A. Meriles, J. Wrachtrup, Nature Commun. 8, 834 (2017). Available as arXiv: 1610.05675v1.

In nanoscale metrology applications, measurements are commonly limited by the performance of the sensor. Here we use a hybrid quantum-classical sensor device to demonstrate  NMR spectral resolution of single spins down to 13 Hz. This work paves the way for high resolution NMR spectroscopy on nanoscopic quantum systems down to the single level.

shotanetal_thumbnail“Photo-induced modification of single photon emitters in hexagonal boron nitride”, Z. Shotan, H. Jayakumar, C.R. Considine, M. Mackoit, H. Fedder, J. Wrachtrup, A. Alkauskas, M.W. Doherty, V.M. Menon, C.A. Meriles, ACS Photonics  3, 2490 (2016) . 

We uncover singular phenomenology in the emission of individual fluorescent defects in boron nitride exposed to suitable laser pulses.

Screen Shot 2016-05-05 at 7.27.02 PMLong-term data storage in diamond”, S. Dhomkar, J. Henshaw, H. Jayakumar, C.A. Meriles, Science Adv. 2, e1600911 (2016). Available as arXiv:1610.09022

We use NV centers in diamond to demonstrate high-density, three-dimensional read/writing of classical information. We also show how nuclear spins can serve as ancillary memories for sub-diffraction data encoding.

NV_ElectronBus“Towards a room-temperature spin quantum bus in diamond via optical spin injection, transport and detection”, M.W. Doherty, C.A. Meriles, A. Alkauskas, H. Fedder, M.J. Sellars, N.B. Manson, Phys. Rev. X 6, 041035 (2016). Available as arXiv:1511.08559.

We discuss the use of charge carriers to generate entanglement between remote nuclear spin qubits in diamond at room temperature

Screen Shot 2016-05-05 at 7.24.14 PM“Optical patterning of trapped charge in nitrogen-doped diamond”, H. Jayakumar, J. Henshaw, S. Dhomkar, D. Pagliero, A. Laraoui, N.B. Manson, R. Albu, M.W. Doherty, C.A. Meriles, Nature Commun. 7, 12660 (2016). Also available as arXiv:1609.03085.

We investigate the diffusion and trapping of charge carriers photo-ionized from NVs and P1 centers in diamond. We observe the formation of intriguing patters that we reproduce semi-quantitatively via a model of coupled master equations.

NV_ThermalSensing2“Imaging thermal conductivity with nanoscale resolution using a scanning spin probe”, A. Laraoui, H. Aycock-Rizzo, X. Lu, Y. Gao, E. Riedo, C.A. Meriles, Nature Commun. 6, 8954 (2015). Available as arXiv:1511.06916.

We use nanoparticle-hosted NVs attached to a thermal AFM tip as a local probe to measure the thermal conductivity of heterogeneous systems with nanometer resolution.

Screen Shot 2016-05-05 at 6.10.25 PM“Probing molecular dynamics at the nanoscale via an individual paramagnetic center”, T.M. Staudacher, N. Raatz, S. Pezzagna, J. Meijer, F. Reinhard, C.A. Meriles, J. Wrachtrup, Nature Commun. 6, 8527 (2015). Available as arXiv:1507.05921.

We work with NV centers nanometers below the crystal surface to probe the near-surface dynamics of molecules from organic systems including solid films and liquids. For the latter group, we manage to separately identify adsorbed and freely diffusing molecules.

 NV5“Dynamic nuclear spin polarization of liquids and gases in contact with nanostructured diamond”, D. Abrams, M.E. Trusheim, D. Englund, M.D. Shattuck, C.A. Meriles, Nano Lett. 14, 2471 (2014).

We discuss the use of near-surface NV centers to polarize the nuclear spins from organic molecules within arbitrary fluids brought in direct contact with the diamond surface.

NV_Nanoparticles1“Scalable Fabrication of High Purity Diamond Nanocrystals with Long-Spin-Coherence Nitrogen Vacancy Centers”, M.E. Trusheim, L. Li, A. Laraoui, E.H. Chen, O. Gaathon, H. Bakhru, T. Schroeder, C.A. Meriles, D.R. Englund, Nano Lett. 14, 32 (2014).

We demonstrate record-long spin coherence lifetimes for NVs within engineered, high-purity diamond nanoparticles.

NV_P1CenterPolarization1“Approach to dark spin cooling in a diamond nanocrystal”, A. Laraoui, C.A. Meriles, ACS Nano 7, 3403 (2013). Available as arxiv:1703.03988

We demonstrate efficient spin polarization transfer from NVs to P1 centers in their vicinity. Further, using the NVs as a local probe, we determine that the P1 center spin polarization reaches up to 50% within a 10 nm volume centered at the NV.

NV_Correlations1“High-Resolution Correlation Spectroscopy of 13C Spins Near a Nitrogen-Vacancy Center in Diamond”, A. Laraoui, F. Dolde, C. Burk, F. Reinhard, J. Wrachtrup, C.A. Meriles, Nature Commun. 4, 1651 (2013). Available as arXiv:1305.1536.

We introduce a new NV-based technique to probe weakly coupled nuclear spins. Unlike prior approaches, this method exploits the long NV spin-lattice relaxation times to attain highly-resolved NMR spectra from the nuclear spin noise.

NV_ProtonSensing2“Nuclear magnetic resonance spectroscopy on a (5nm)3 volume of liquid and solid samples”, T. Staudacher, F. Shi, S. Pezzagna, J. Meijer, J. Du, C.A. Meriles, F. Reinhard, J. Wrachtrup, Science 339, 561 (2013).

We demonstrate for the first time detection the use of shallow NVs to probe nuclear spins from an arbitrary organic system deposited on the diamond surface.

NV_DetectingP1Centers“Nitrogen-Vacancy-assisted magnetometry of paramagnetic centers in an individual diamond nanocrystal”, A. Laraoui, J.S. Hodges, C.A. Meriles, Nano Lett. 12, 3477 (2012).

We use double resonance techniques to probe P1 centers contained in an individual diamond nanocrystal.

OPinGalliumArsenide1“Optically re-writable patterns of nuclear magnetization in Gallium Arsenide”, J.P. King, Y. Li, C.A. Meriles, J.A. Reimer, Nature Commun. 3, 918 (2012).

We use the large magnetic field gradient to image the nuclear spin polarization induced by optical pumping of a gallium arsenide wafer. We show that low illumination intensities generate a non-monotonic polarization profile where nuclear spins polarize positively or negatively, depending on the distance to the sample surface.

FaradayRotationInLiquids2“Magneto-optical contrast in liquid-state optically-detected NMR spectroscopy”, D. Pagliero, C.A. Meriles, Proc. Natl. Acad. Sci. USA 108, 19510 (2011).

We use time-resolved Faraday rotation at 10 T to demonstrate for the first time chemical-shift-resolved NMR of arbitrary solvents.

FaradayRotationInLiquids1“Time-resolved optically-detected NMR of fluids at high-magnetic field”, D. Pagliero, W. Dong, D. Sakellariou, C.A. Meriles, J. Chem. Phys. 133, 154505 (2010).

We demonstrate optical detection of magnetic resonance at high-magnetic field using time-resolved Faraday rotation.

Stay tuned! More coming up soon!