Abstract: A synthetic diamond material comprising one or more spin defects having a full width half maximum intrinsic inhomogeneous zero phonon line width of no more than 100 MHz. The method for obtain such a material involves a multi-stage annealing process.

Abstract: Systems and methods for magnetic sensing and imaging include a sensor having a network of isolated electron-spin quantum bits (qubits) disposed on the surface of the sensor; and a solid state electronic spin system disposed below the surface of the sensor, wherein the solid state electronic spin system has a spin-state dependent fluorescence; a source of light; a source of first external perturbation, wherein the source of first external perturbation generates a magnetic field; a source of second external perturbation; wherein, the source of light and the first and second external perturbations are configured to coherently and independently manipulate the spin states of at least one qubit and at least one solid state electronic spin system; and a detector to optically measure the solid-state electronic spins spin-state dependent fluorescence.

Abstract: Techniques for obtaining a frequency standard using the crystal field splitting frequency of nitrogen vacancy center in diamond are disclosed. In certain exemplary embodiments, a microwave field is applied to the diamond and optically exciting the diamond under green light. The photoluminescent response of the diamond is measured by a photodetector. The intensity of the photoluminescent response can be used to determine the phase shift between the microwave and the crystal field splitting frequency. The microwave field frequency can be adjusted until the phase shift is below a predetermined threshold, and the microwave frequency can then be output for use as a standard.

Abstract: A quantum information processor (QIP) may include a plurality of quantum registers, each quantum register containing at least one nuclear spin and at least one localized electronic spin. At least some of the quantum registers may be coherently coupled to each other by a dark spin chain that includes a series of optically unaddressable spins. Each quantum register may be optically addressable, so that quantum information can be initialized and read out optically from each register, and moved from one register to another through the dark spin chain, though an adiabatic sequential swap or through free-fermion state transfer. A scalable architecture for the QIP may include an array of super-plaquettes, each super-plaquette including a lattice of individually optically addressable plaquettes coupled to each other through dark spin chains, and separately controllable by confined microwave fields so as to permit parallel operations.

Abstract: An approach to nanoscale thermometry that utilizes coherent manipulation of the electronic spin associated with nitrogen-vacancy (NV) color centers in diamond is disclosed. The methods and apparatus allow for detection of temperature variations down to milli-Kelvin resolution, at nanometer length scales. This biologically compatible approach to thermometry offers superior temperature sensitivity and reproducibility with a reduced measurement time. The disclosed apparatus can be used to study heat-generating intracellular processes.

Abstract: A synthetic diamond material comprising one or more spin defects having a full width half maximum intrinsic inhomogeneous zero phonon line width of no more than 100 MHz. The method for obtain such a material involves a multi-stage annealing process.

Abstract: An etch mask is formed on a substrate. The substrate is positioned in an enclosure configured to shield an interior of the enclosure from electromagnetic fields exterior to the enclosure; and the substrate is etched in the enclosure, including removing a portion of the substrate to form a structure having at least a portion that is isolated and/or suspended over the substrate.

Abstract: An etch mask is formed on a substrate. The substrate is positioned in an enclosure configured to shield an interior of the enclosure from electromagnetic fields exterior to the enclosure; and the substrate is etched in the enclosure, including removing a portion of the substrate to form a structure having at least a portion that is isolated and/or suspended over the substrate.

Abstract: Techniques for obtaining a frequency standard using the crystal field splitting frequency of nitrogen vacancy center in diamond are disclosed. In certain exemplary embodiments, a microwave field is applied to the diamond and optically exciting the diamond under green light. The photoluminescent response of the diamond is measured by a photodetector. The intensity of the photoluminescent response can be used to determine the phase shift between the microwave and the crystal field splitting frequency. The microwave field frequency can be adjusted until the phase shift is below a predetermined threshold, and the microwave frequency can then be output for use as a standard.

Abstract: A quantum information processor (QIP) may include a plurality of quantum registers, each quantum register containing at least one nuclear spin and at least one localized electronic spin. At least some of the quantum registers may be coherently coupled to each other by a dark spin chain that includes a series of optically unaddressable spins. Each quantum register may be optically addressable, so that quantum information can be initialized and read out optically from each register, and moved from one register to another through the dark spin chain, though an adiabatic sequential swap or through free-fermion state transfer. A scalable architecture for the QIP may include an array of super-plaquettes, each super-plaquette including a lattice of individually optically addressable plaquettes coupled to each other through dark spin chains, and separately controllable by confined microwave fields so as to permit parallel operations.

Abstract: A method is disclosed for increasing the sensitivity of a solid state electronic spin based magnetometer that makes use of individual electronic spins or ensembles of electronic spins in a solid-state lattice, for example NV centers in a diamond lattice. The electronic spins may be configured to undergo a Zeeman shift in energy level when photons of light are applied to the electronic spins followed by pulses of an RF field that is substantially transverse to the magnetic field being detected. The method may include coherently controlling the electronic spins by applying to the electronic spins a sequence of RF pulses that dynamically decouple the electronic spins from mutual spin-spin interactions and from interactions with the lattice. The sequence of RF pulses may be a Hahn spin-echo sequence, a Can Purcell Meiboom Gill sequence, or a MREV8 pulse sequence, by way of example.

Abstract: A cavity free, broadband approach for engineering photon emitter interactions via sub-wavelength confinement of optical fields near metallic nanostructures. When a single CdSe quantum dot (QD) is optically excited in close proximity to a silver nanowire (NW), emission from the QD couples directly to guided surface plasmons in the NW, causing the wire's ends to light up. Nonclassical photon correlations between the emission from the QD and the ends of the NW demonstrate that the latter stems from the generation of single, quantized plasmons. Results from a large number of devices show that the efficient coupling is accompanied by more than 2.5-fold enhancement of the QD spontaneous emission, in a good agreement with theoretical predictions.

Abstract: The invention provides systems and methods enabling high fidelity quantum communication over long communication channels even in the presence of significant loss in the channels. The invention involves laser manipulation of quantum correlated atomic ensembles using linear optic components (110, 120), optical sources of low intensity pulses (10), interferers in the form of beam splitters (150), and single-photon detectors (180, 190) requiring only moderate efficiencies. The invention provides fault-tolerant entanglement generation and connection using a sequence of steps that each provide built-in entanglement purification and that are each resilient to realistic noise levels. The invention relies upon collective rather single particle excitations in atomic ensembles and results in communication efficiency scaling polynomially with the total length of the communication channel.

Abstract: Apparatus and methods for high fidelity quantum communication over long communication channels even in the presence of significant loss in the channels are disclosed. The invention employs laser manipulation of quantum correlated atomic ensembles using linear optic components, optical sources of low intensity pulses, beam splitters, and single-photon detectors requiring only moderate efficiencies. The invention provides fault-tolerant entanglement generation and connection, using a sequence of steps that each provide built-in entanglement purification and that are each resilient to the realistic noise. The invention relies upon collective excitation in atomic ensembles rather than single particle excitations in atomic ensembles so that communication efficiency scales polynomially with the total length of a communication channel.