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The authors of this paper accept the reality of the phenomenon of repression and consider that it alone explains many kinds of psychopathology. Nevertheless, the assumption in Freud's sketch of the mechanism of repression that the ego continually guards against the repressed impulse becoming conscious creates a logical problem. That would require that the(More)
Object-relations theory implicitly assumes primary drives to cope with the fact that some kinds of transaction with objects are not gratifying but are feared and avoided. Fairbairn's conception of motivation assumes that there is an independent primary drive which may be called 'need for love', independent of other gratifications. Such an instinctual-drive(More)
Detection of weak magnetic fields with nanoscale spatial resolution is an outstanding problem in the biological and physical sciences. For example, at a distance of 10 nm, the spin of a single electron produces a magnetic field of about 1 muT, and the corresponding field from a single proton is a few nanoteslas. A sensor able to detect such magnetic fields(More)
  • L Jiang, J S Hodges, J R Maze, P Maurer, J M Taylor, D G Cory +5 others
  • 2009
Robust measurement of single quantum bits plays a key role in the realization of quantum computation and communication as well as in quantum metrology and sensing. We have implemented a method for the improved readout of single electronic spin qubits in solid-state systems. The method makes use of quantum logic operations on a system consisting of a single(More)
The development of a robust light source that emits one photon at a time will allow new technologies such as secure communication through quantum cryptography. Devices based on fluorescent dye molecules, quantum dots and carbon nanotubes have been demonstrated, but none has combined a high single-photon flux with stable, room-temperature operation.(More)
Design of a doubly-clamped beam structure capable of localizing mechanical and optical energy at the nanoscale is presented. The optical design is based upon photonic crystal concepts in which patterning of a nanoscale-cross-section beam can result in strong optical localization to an effective optical mode volume of 0.2 cubic wavelengths (λ c) 3. By(More)
We describe a method to enhance the sensitivity of precision measurements that takes advantage of the environment of a quantum sensor to amplify the response of the sensor to weak external perturbations. An individual qubit is used to sense the dynamics of surrounding ancillary qubits, which are in turn affected by the external field to be measured. The(More)
Multi-qubit systems are crucial for the advancement and application of quantum science. Such systems require maintaining long coherence times while increasing the number of qubits available for coherent manipulation. For solid-state spin systems, qubit coherence is closely related to fundamental questions of(More)
Magnetic resonance imaging can characterize and discriminate among tissues using their diverse physical and biochemical properties. Unfortunately, submicrometer screening of biological specimens is presently not possible, mainly due to lack of detection sensitivity. Here we analyze the use of a nitrogen-vacancy center in diamond as a magnetic sensor for(More)
We present the design, fabrication, and characterization of high quality factor (Q ~10 3) and small mode volume (V ~0.75 (λ/n) 3) planar photonic crystal cavities from cubic (3C) thin films (thickness ~200 nm) of silicon carbide (SiC) grown epitaxially on a silicon substrate. We demonstrate cavity resonances across the telecommunications band, with(More)