A novel method for the synthesis of highly monodispersed hydrophillic InP−ZnS nanocrystals and their use as luminescence probes live cell imaging is reported. Hydrophobic are prepared by a new that yields high-quality, luminescent core−shell within 6−8 h total reaction time. Then carefully manipulating surface these passivated nanocrystals, aqueous dispersions folate-conjugated (folate-QDs) with high photostability prepared. By confocal microscopy, we demonstrate receptor-mediated delivery...

Cooperative phenomena stemming from radiation-field-mediated coupling between individual quantum emitters are presently attracting broad interest for on-chip photonic memories and longrange entanglement.Common to these applications is the generation of electro-magnetic modes over macroscopic distances.Much research, however, still needed before such systems can be deployed in form practical devices, starting with investigation alternate physical platforms.Quantum two-dimensional (2D) provide...

The strong confinement of semiconductor excitons in a quantum dot gives rise to atom-like behavior. full benefit such structure is best observed resonant excitation where the excited state can be deterministically populated and coherently manipulated. Due large refractive index device geometry it remains challenging observe resonantly emission that free from laser scattering III/V self-assembled dots. Here we exploit biexciton binding energy create an extremely clean single photon source via...

Fluorescent defects recently observed under ambient conditions in hexagonal boron nitride (h-BN) promise to open novel opportunities for the implementation of on-chip photonic devices that rely on identical photons from single emitters. Here we report room-temperature photoluminescence dynamics individual emitters multilayer h-BN flakes exposed blue laser light. Comparison optical spectra recorded at successive times reveals considerable spectral diffusion, possibly result slowly...

The negatively charged nitrogen vacancy (NV-) center in diamond is the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Although most work so far has focused on NV- optical and spin properties, control charge state promises complementary opportunities. One intriguing possibility long-term storage information, a notion we hereby introduce using NV-rich, type 1b diamond. As proof principle, use multicolor microscopy read, write,...

Optomechanical devices sensitively transduce and actuate motion of nanomechanical structures using light. Single--crystal diamond promises to improve the performance optomechanical devices, while also providing opportunities interface nanomechanics with color center spins related quantum technologies. Here we demonstrate dissipative waveguide--optomechanical coupling exceeding 35 GHz/nm nanobeams supporting both optical waveguide modes mechanical resonances, use this measure nanobeam...

Sensors in optical cavities can be used for measuring acceleration, fields, and particles. New research reveals a record sensitivity detecting small amounts of torque within cavities, useful magnetic fields.

Diamond's nitrogen vacancy (NV) center is an optically active defect with long spin coherence times, showing great potential for both efficient nanoscale magnetometry and quantum information processing schemes. Recently, the formation of buried 3D optical waveguides high quality single NVs in diamond were demonstrated using versatile femtosecond laser-writing technique. However, until now, combining these technologies has been outstanding challenge. In this work, we fabricate laser written...

Resonant second harmonic generation between 1550 nm and 775 with normalized outside efficiency >3.8×10−4 mW−1 is demonstrated in a gallium phosphide microdisk supporting high-Q modes at visible (Q∼104) infrared (Q∼105) wavelengths. The double resonance condition satisfied for specific pump power through intracavity photothermal temperature tuning using ∼360 μW of light input to fiber taper coupled resonance. Power dependent consistent simple model thermal the observed.

Although the spin properties of superficial shallow nitrogen-vacancy (NV) centers have been subject extensive scrutiny, considerably less attention has devoted to studying dynamics NV charge conversion near diamond surface. Using multicolor confocal microscopy, here we show that near-surface point defects arising from high-density ion implantation dramatically increase ionization and recombination rates NVs compared those in bulk diamond. Further, find these grow linearly, not quadratically,...

Abstract The nitrogen-vacancy (NV) centre in diamond is emerging as a promising platform for solid-state quantum information processing and nanoscale metrology. Of interest these applications the manipulation of NV charge, which can be attained by optical excitation. Here, we use two-colour microscopy to investigate dynamics photo-ionization, charge diffusion trapping type-1b diamond. We combine fixed-point laser excitation scanning fluorescence imaging locally alter concentration negatively...

Abstract Integration of quantum emitters in photonic structures is an important step the broader quest to generate and manipulate on-demand single photons via compact solid-state devices. Unfortunately, implementations relying on material platforms that also serve as emitter host often suffer from a tradeoff between desired properties system practicality performance. Here, we demonstrate “pick place” integration Si 3 N 4 microdisk optical resonator with bright form ∼20-nm-thick hexagonal...

The development of linear quantum computing within integrated circuits demands high quality semiconductor single photon sources. In particular, for a reliable source it is not sufficient to have low multi-photon component, but also possess efficiency. We investigate the statistics emission from dot with method that able sensitively detect trade-off between efficiency and contribution. Our measurements show, light emitted when resonantly excited very content. Additionally, we demonstrated,...

The silicon vacancy (SiV) center in diamond is typically found three stable charge states, SiV0, SiV-, and SiV2-, but studying the processes leading to their formation challenging, especially at room temperature, due starkly different photoluminescence rates. Here, we use confocal fluorescence microscopy activate probe interconversion between all states under ambient conditions. In particular, witness of SiV0 via two-step capture diffusing, photogenerated holes, a process expose both through...

A broad effort is underway to understand and harness the interaction between superconductors spin-active color centers with an eye on hybrid quantum devices novel imaging modalities of superconducting materials. Most work, however, overlooks interplay either system environment created by center host. Here we use a diamond scanning probe investigate spin dynamics single nitrogen-vacancy (NV) proximal film. We find that presence superconductor increases NV coherence lifetime, phenomenon...

Photons which are generated in a two-photon cascade process have an underlying time correlation since the spontaneous emission of upper level populates intermediate state. This leads to reduction purity photon emitted from Here we characterize this for biexciton-exciton InAs/GaAs quantum dot. We show that can be reduced by tuning biexciton transition resonance planar distributed Bragg reflector cavity. The enhanced and inhibited into cavity accelerates slows down exciton thus reduces...

We demonstrate optical readout of ensembles nitrogen-vacancy(NV) center spins in a bulk diamond sample via spin-to-charge conversion. A high power 594 nm laser is utilized to selectively ionize these paramagnetic defects the spin state with contrast up 12%. In comparison conventional 520 readout, spin-to-charge-conversion-based provides higher signal-to-noise ratio, tenfold sensing measurement speedup for millisecond long pulse sequences. This level performance was achieved an NV- ionization...

While the study of space charge potentials has a long history, present models are largely based on notion steady state equilibrium, ill-suited to describe wide bandgap semiconductors with moderate low concentrations defects. Here we build color centers in diamond both locally inject carriers into crystal and probe their evolution as they propagate presence external internal potentials. We witness formation metastable patterns whose shape - concomitant field can be engineered through timing...

Perception and behavior require coordinated activity of thousands neurons operating in networks that span millimeters brain area. In vivo calcium imaging approaches have proven exceptionally powerful for examining the structure these at large scales, optogenetics can allow causal manipulations populations neurons. However, realizing full potential techniques requires ability to simultaneously measure manipulate distinct circuit elements on scale millimeters.

Although chemical vapor deposition (CVD) is one of the preferred routes to synthetic diamond crystals, a full knowledge point defects produced during growth still incomplete. Here we exploit charge and spin properties nitrogen-vacancy (NV) centers in type-1b CVD expose an optically magnetically dark defect, so far virtually unnoticed despite abundance comparable (if not greater than) that substitutional nitrogen. Indirectly-detected photo-luminescence spectroscopy indicates donor state 1.6...

We report on the room-temperature single photon emission dynamics originating from defect states in hBN. Photo induced modification of characteristics thee defects under blue and green illumination is shown.

We articulate confocal microscopy and electron spin resonance to implement spin-to-charge conversion in a small ensemble of nitrogen-vacancy (NV) centers bulk diamond, demonstrate charge neighboring defects conditional on the NV state. build this observation show time-resolved manipulation ancilla-charge-aided state detection via integrated measurements. Our results hint at intriguing opportunities search for enhanced forms color-center-based metrology information processing down limit...