A5033073814- Quantum Information and Cryptography
- Quantum and electron transport phenomena
- Atomic and Subatomic Physics Research
- Quantum optics and atomic interactions
- Mechanical and Optical Resonators
- Quantum Mechanics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Computing Algorithms and Architecture
- Electron Spin Resonance Studies
- Physics of Superconductivity and Magnetism
- Advanced NMR Techniques and Applications
- Diamond and Carbon-based Materials Research
- Photonic and Optical Devices
- Spectroscopy and Quantum Chemical Studies
- Force Microscopy Techniques and Applications
- Semiconductor materials and devices
- Laser-Matter Interactions and Applications
- Advanced Chemical Physics Studies
- Advanced Fiber Laser Technologies
- Spectroscopy and Laser Applications
- Crystallography and Radiation Phenomena
- Magnetic properties of thin films
- Terahertz technology and applications
- Luminescence Properties of Advanced Materials
- Advanced Electron Microscopy Techniques and Applications
Service de Physique de l'État Condensé
2008-2025
Centre National de la Recherche Scientifique
2016-2025
Institut Rayonnement-Matière de Saclay
2012-2025
CEA Paris-Saclay
2016-2025
Université Paris-Saclay
2016-2025
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2016-2025
CEA Paris-Saclay - Etablissement de Saclay
2024-2025
DSM (Netherlands)
2008-2014
Delft University of Technology
2004-2009
Laboratoire Kastler Brossel
2000-2006
An extensively pursued current direction of research in physics aims at the development practical technologies that exploit effects quantum mechanics. As part this ongoing effort, devices for information processing, secure communication, and high-precision sensing are being implemented with diverse systems, ranging from photons, atoms, spins to mesoscopic superconducting nanomechanical structures. Their physical properties make some these systems better suited than others specific tasks;...
After quantum particles have interacted, they generally remain in an entangled state and are correlated at a distance by quantum-mechanical links that can be used to transmit process information nonclassical ways. This implies programmable sequences of operations generate analyze the entanglement complex systems. We demonstrated such procedure for two atoms single-photon cavity mode, engineering analyzing three-particle succession controlled steps address individually. entangling can,...
Following a recent proposal by S. B. Zheng and G. C. Guo (Phys. Rev. Lett. 85, 2392 (2000)), we report an experiment in which two Rydberg atoms crossing non-resonant cavity are entangled coherent energy exchange. The process, mediated the virtual emission absorption of microwave photon, is characterized collision mixing angle four orders magnitude larger than for colliding free space with same impact parameter. final state controlled adjusting atom-cavity detuning. This procedure,...
We have realized a quantum phase gate operating on bits carried by single Rydberg atom and zero- or one-photon field in high- $Q$ cavity. The operation is based the dephasing of atom-field state produced full cycle Rabi oscillation. angle, conditioned to initial state, can be adjusted over wide range tuning atom-cavity frequency difference. demonstrate that preserves qubit coherence generates entanglement. This an essential tool for nondestructive measurement photons manipulation many-qubit...
We report the experimental realization of a hybrid quantum circuit combining superconducting qubit and an ensemble electronic spins. The qubit, transmon type, is coherently coupled to spin consisting nitrogen-vacancy (NV) centers in diamond crystal via frequency-tunable resonator acting as bus. Using this circuit, we prepare arbitrary superpositions states that store into collective excitations retrieve back later on qubit. These results constitute first proof concept spin-ensemble based...
Coherent control of quantum states has been demonstrated in a variety superconducting devices. In all these devices, the variables that are manipulated collective electromagnetic degrees freedom: charge, phase, or flux. Here, we demonstrate coherent manipulation system based on Andreev bound states, which microscopic quasiparticle inherent to weak links. Using circuit electrodynamics setup perform single-shot readout this "Andreev qubit". We determine its excited state lifetime and coherence...
We have measured the complete Wigner function W of vacuum and a single-photon state for field stored in high-Q cavity. This experiment implements direct Lutterbach Davidovich method [L. G. L. Davidovich, Phys. Rev. Lett. 78, 2547 (1997)]] is based on dispersive interaction single circular Rydberg atom with cavity field. The nonclassical nature exhibited by region negative values. Extensions to other states are discussed.
Using a single circular Rydberg atom, we have prepared two modes of superconducting cavity in maximally entangled state. The share photon. This entanglement is revealed by second atom probing, after delay, the correlations between modes. experiment opens interesting perspectives for quantum information manipulation and fundamental tests theory.
A two-photon Fock state is prepared in a cavity sustaining "source mode" and "target mode," with single circular Rydberg atom. In third-order Raman process, the atom emits photon target while scattering one from source into target. The final probed by measuring Ramsey interferometry light shifts induced field on same Extensions to other multiphoton processes new type of micromaser are briefly discussed.
We present measurements of superconducting flux qubits embedded in a three dimensional copper cavity. The are fabricated on sapphire substrate and measured by coupling them inductively to an on-chip resonator located the middle At their flux-insensitive point, all reach intrinsic energy relaxation time 6-20 μs range pure dephasing comprised between 3 10 μs. This significant improvement over previous works opens way coherent qubit individual spins.
We propose a multi-mode quantum memory protocol able to store the state of field in microwave resonator into an ensemble electronic spins. The stored information is protected against inhomogeneous broadening spin by spin-echo techniques resulting times orders magnitude longer than previously achieved. By calculating evolution first and second moments spin-cavity system variables for realistic experimental parameters, we show that based on NV center spins diamond can qubit encoded |0> |1>...
We report the characterization of a two-qubit processor implemented with two capacitively coupled tunable superconducting qubits transmon type, each qubit having its own non-destructive single-shot readout. The fixed capacitive coupling yields \sqrt{iSWAP} gate for suitable interaction time. reconstruct by state tomography coherent dynamics two-bit register as function time, observe violation Bell inequality 22 standard deviations after correcting readout errors, and measure quantum process...
Quantum computing promises to tackle computational problems that are intractable with classical computers. Researchers demonstrate spin ensembles can store quantum information over longer times than previously achieved, a significant step toward memory.
We analyze the impact of electric field and magnetic fluctuations in decoherence electronic spin associated with a single nitrogen-vacancy (NV) defect diamond. To this end, we tune amplitude order to engineer eigenstates protected either against noise or noise. The competition between these sources is analyzed quantitatively by changing their relative strength through modifications host diamond material. This study provides significant insights into NV spin, which valuable for quantum...
A scheelite crystal with residual concentration of erbium is cooled down to 10 mK, yielding a record spin coherence time 23 ms.
We propose a scheme to couple two superconducting charge or flux qubits biased at their symmetry points with unequal energy splittings. Modulating the coupling constant between sum difference of frequencies allows bring them into resonance in rotating frame. Switching on and off modulation amounts switching which can be realized nanosecond speed. discuss various physical implementations this idea, find that our lead rapid operation two-qubit gate.
We report electron spin resonance spectroscopy measurements performed at millikelvin temperatures in a custom-built spectrometer comprising superconducting micro-resonator $7$ GHz and Josephson parametric amplifier. Owing to the small ${\sim}10^{-12}\lambda^3$ magnetic resonator mode volume low noise of amplifier, sensitivity reaches $260\pm40$ spins$/$echo $65\pm10$ $\mathrm{spins}/\sqrt{\text{Hz}}$, respectively.