Related papers: Single-Electron Measurements with a Micromechanica…

We use fast coherent reflectivity measurements, in a strongly-coupled quantum dot-micropillar device, to monitor in real-time single-charge jumps at the microsecond timescale. Thanks to the strong enhancement of light-matter interaction…

We analyze the requirements to test some of the most paradigmatic collapse models with a protocol that prepares quantum superpositions of massive objects. This consists of coherently expanding the wave function of a ground-state-cooled…

We study the behavior of a quantum gyroscope, that is, a quantum system which singles out a direction in space in order to measure certain properties of incoming particles such as the orientation of their spins. We show that repeated…

We study an influence of the continuous measurement in a composite quantum system C on the evolution of the states of its parts. It is shown that the character of the evolution (decoherence or recoherence) depends on the type of the…

Coherent superpositions are one of the hallmarks of quantum mechanics and are vital for any quantum mechanical device to outperform the classically achievable. Generically, superpositions are verified in interference experiments, but…

We study the role of the electromagnetic field's frequency in time precision measurements using single photons as a paradigmatic system. For such, we independently identify the contributions of intensity and spectral resources and show that…

Low-capacitance Josephson junction systems as well as coupled quantum dots, in a parameter range where single charges can be controlled, provide physical realizations of quantum bits, discussed in connection with quantum computing. The…

In this perspective, the various measures of electron correlation used in wavefunction theory, density functional theory and quantum information theory are briefly reviewed. We then focus on a more traditional metric based on dominant…

Single electron charging in an individual InAs quantum dot was observed by electrostatic force measurements with an atomic force microscope (AFM). The resonant frequency shift and the dissipated energy of an oscillating AFM cantilever were…

Measurement and fluctuations are closely related to each other in quantum mechanics. This fact is explicitly demonstrated in the case of a quantum non-demolition photodetector which is composed of a double quantum-wire electron…

Determination of the path taken by a quantum particle leads to a suppression of interference and to a classical behavior. We employ here a quantum 'which path' detector to perform accurate path determination in a…

Superconducting qubits are a leading platform for scalable quantum computing and quantum error correction. One feature of this platform is the ability to perform projective measurements orders of magnitude more quickly than qubit…

In a recent paper, cond-mat/0405331 (Ref. 1), del Barco et al. reported experimental studies on a Ni4 molecular system. They used an experimental method (combining microwave spectroscopy with high sensitivity magnetic measurements) that we…

When a two-level system -- a qubit -- is used as a probe of a larger system, it naturally leads to answering a single yes-no question about the system state. Here we propose a method where a single qubit is able to extract, not a single,…

We study an optomechanical system in which a microwave field and an optical field are coupled to a common mechanical resonator. We explore methods that use these mechanical resonators to store quantum mechanical states and to transduce…

We construct a low-temperature microwave waveguide interferometer for measuring high-frequency properties of two-dimensional electron gases (2DEGs). Coupled plasmon-cyclotron resonance (PCR) spectra are used to extract effective mass, bulk…

We use time-resolved charge detection techniques to investigate single-electron tunneling in semiconductor quantum dots. The ability to detect individual charges in real-time makes it possible to count electrons one-by-one as they pass…

We study a general model describing a self-detecting single electron transistor realized by a suspended carbon nanotube actuated by a nearby antenna. The main features of the device, recently observed in a number of experiments, are…

We measure the mechanical thermal noise of soft silicon atomic force microscopy cantilevers. Using an interferometric setup, we have a resolution down to 1E-14 m/rtHz on a wide spectral range (3 Hz to 1E5 Hz). The low frequency behavior…

Optomechanics is currently believed to provide a promising route towards the achievement of genuine quantum effects at the large, massive-system scale. By using a recently proposed figure of merit that is well suited to address…