Reconstruction of non-classical cavity field states with snapshots of their decoherence

  title={Reconstruction of non-classical cavity field states with snapshots of their decoherence},
  author={Samuel Deleglise and Igor Dotsenko and Cl{\'e}ment Sayrin and Julien Bernu and M. Brune and Jean-Michel Raimond and Serge Haroche},
The state of a microscopic system encodes its complete quantum description, from which the probabilities of all measurement outcomes are inferred. Being a statistical concept, the state cannot be obtained from a single system realization, but can instead be reconstructed from an ensemble of copies through measurements on different realizations. Reconstructing the state of a set of trapped particles shielded from their environment is an important step in the investigation of the quantum… 

Generation and reconstruction of schrödinger cat states of light in a cavity by quantum nondemolition measurements

  • I. DotsenkoS. Deleglise S. Haroche
  • Physics
    CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference
  • 2009
The quantum nondemolition (QND) method for photon counting, recently developed at ENS [1,2], can be used for determining the photon number distribution of a light field by repeating the measurement

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Deterministic Creation of Macroscopic Cat States

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Quantum decoherence of a single ion qubit induced by photon-number fluctuations

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It is demonstrated how the quantum features of two single-photon counters vanish under the influence of a noisy environment and experimentally witness the transition between the full-quantum operation of the measurement device to the "semi-classical regime", described by a positive Wigner function.



Generation of optical ‘Schrödinger cats’ from photon number states

A protocol is demonstrated that allows the generation of arbitrarily large squeezed Schrödinger cat states, using homodyne detection and photon number states as resources, and clearly exhibits several quantum phase-space interference fringes between the ‘dead’ and ‘alive’ components.

Progressive field-state collapse and quantum non-demolition photon counting

The observation of such a step-by-step collapse by non-destructively measuring the photon number of a field stored in a cavity is reported, which illustrates all the postulates of quantum measurement (state collapse, statistical results and repeatability) and should facilitate studies of non-classical fields trapped in cavities.

Decoherence of quantum superpositions through coupling to engineered reservoirs

Decoherence is induced by coupling the atom to engineered reservoirs, in which the coupling and state of the environment are controllable, and the decoherence rate scales with the square of a quantity describing the amplitude of the superposition state.

Decoherence, einselection, and the quantum origins of the classical

as quantum engineering. In the past two decades it has become increasingly clear that many (perhaps all) of the symptoms of classicality can be induced in quantum systems by their environments. Thus

Manipulating quantum entanglement with atoms and photons in a cavity

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Quantum state reconstruction of the single-photon Fock state.

The quantum state of optical pulses containing single photons is reconstructed using the method of phase-randomized pulsed optical homodyne tomography and shows a strong dip reaching classically impossible negative values around the origin of the phase space.

A proposal to test Bell’s inequalities with mesoscopic non-local states in cavity QED

Abstract.We propose a cavity quantum electrodynamics (CQED) experiment to test the violation of a Bell-type inequality using non-local mesoscopic states (NLMS). These states involve coherent field

Tomographic reconstruction of the single-photon Fock state by high-frequency homodyne detection

A single-photon Fock state has been generated by means of conditional preparation from a two-photon state emitted in the process of spontaneous parametric down-conversion. A recently developed

Experimental Determination of the Motional Quantum State of a Trapped Atom.

Using novel reconstruction schemes, both the density matrix in the number state basis and the Wigner function are determined, which are sensitive indicators of decoherence in the system.