A5020911694- Advanced Fiber Laser Technologies
- Quantum Information and Cryptography
- Advanced Frequency and Time Standards
- Cold Atom Physics and Bose-Einstein Condensates
- Mechanical and Optical Resonators
- Quantum Mechanics and Applications
- Photonic and Optical Devices
- Solid State Laser Technologies
- Quantum Computing Algorithms and Architecture
- Quantum, superfluid, helium dynamics
- Atomic and Subatomic Physics Research
- Spectroscopy and Laser Applications
- Force Microscopy Techniques and Applications
- Quantum optics and atomic interactions
- Laser-Matter Interactions and Applications
- Advanced Measurement and Metrology Techniques
- Electrochemical Analysis and Applications
- Analytical Chemistry and Sensors
- Geophysics and Sensor Technology
- Advanced Thermodynamics and Statistical Mechanics
- Semiconductor Quantum Structures and Devices
- Mass Spectrometry Techniques and Applications
- Advanced MEMS and NEMS Technologies
- Semiconductor Lasers and Optical Devices
- Acoustic Wave Resonator Technologies
Institut Néel
2011-2025
Centre National de la Recherche Scientifique
2011-2025
Université Grenoble Alpes
2008-2025
Institut polytechnique de Grenoble
2019-2025
Institut Universitaire de France
2016-2021
Institut d’Optique Graduate School
2002-2020
International University of Fundamental Studies
2016
Université Joseph Fourier
2009-2013
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2009
CEA Grenoble
2009
A key requirement for scalable quantum computing is that elementary gates can be implemented with sufficiently low error. One method determining the error behavior of a gate implementation to perform process tomography. However, standard tomography limited by errors in state preparation, measurement and one-qubit gates. It suffers from inefficient scaling number qubits does not detect adverse error-compounding when are composed long sequences. An additional problem due fact desirable...
Individual laser-cooled 24Mg+ ions are confined in a linear Paul trap with novel geometry where gold electrodes located single plane and the trapped 40 microm above this plane. The relatively simple design fabrication procedure important for large-scale quantum information processing (QIP) using ions. Measured ion motional frequencies compared to simulations. Measurements of recooling after cooling is temporarily suspended yield heating rate approximately 5 quanta per millisecond frequency...
We report on the design, fabrication, and preliminary testing of a 150 zone array built in `surface-electrode' geometry microfabricated single substrate. demonstrate transport atomic ions between legs `Y'-type junction measure in-situ heating rates for ions. The trap design demonstrates use basic component library that can be quickly assembled to form structures optimized particular experiment.
We analyze the error in trapped-ion, hyperfine qubit, quantum gates due to spontaneous scattering of photons from gate laser beams. investigate single-qubit rotations that are based on stimulated Raman transitions and two-qubit entangling phase-gates spin-dependent optical dipole forces. This is compared between different ion species currently being investigated as possible information carriers. For both types we show with realistic powers can be reduced below current estimates...
We have measured motional heating rates of trapped atomic ions, a factor that can influence multi-ion quantum logic gate fidelities. Two simplified techniques were developed for this purpose: one relies on Raman sideband detection implemented with single laser source, while the second is even simpler and based time-resolved fluorescence during Doppler recooling. applied these methods to determine in microfrabricated surface-electrode trap made gold fused quartz, which traps ions...
We investigate the temporal dynamics of Doppler cooling an initially hot single trapped atom in weak binding regime using a semiclassical approach. develop analytical model for simplest case vibrational mode harmonic trap, and show how this allows us to estimate initial energy particle by observing fluorescence rate during process. The experimental implementation temperature measurement provides way measure heating rates rise absence cooling. This method is technically relatively simple...
It was recently proposed to use small groups of trapped ions as qubit carriers in miniaturized electrode arrays that comprise a large number individual trapping zones, between which could be moved. This approach might scalable for quantum information processing with numbers qubits. Processing is achieved by transporting and from separate memory manipulation zones logic operations. The transport ion this scheme plays major role requires precise experimental control fast transport. In paper we...
We explore the properties of ultranarrow spectral holes in ensembles solid-state emitters crystals over a range sub-kelvin temperatures, as new step toward leveraging their exceptional coherence more effectively. As an example, we consider potential gain observed application frequency stabilization schemes. investigate how parameters used to burn hole impact its shape, and these factors determine minimum achievable linewidth. In addition stability hole's center frequency, linewidth contrast...
The light emission rate of a single quantum dot can be drastically enhanced by embedding it in resonant semiconductor microcavity. This phenomenon is known as the Purcell effect, and coupling strength between emitter cavity quantified factor. most natural way for probing effect time-resolved measurement. However, this approach not always convenient one, alternative approaches based on continuous-wave measurement are often more appropriate. Various signatures indeed observed using...
Frequency-locking a laser to spectral hole in rare-earth doped crystals at cryogenic temperature has been shown be promising alternative the use of high finesse Fabry-Perot cavities when seeking very short term stability (M. J. Thorpe et al., Nature Photonics 5, 688 (2011)). We demonstrate here novel technique for achieving such stabilization, based on generating heterodyne beat-note between master and slave whose dephasing caused by propagation near generate error signal frequency lock. The...
By spectrally hole burning an inhomogeneously broadened ensemble of ions while applying a controlled perturbation, one can obtain spectral holes that are functionalized for maximum sensitivity to different perturbations. We propose use such hole-burned structures the dispersive optical interaction with rare-earth-ion dopants whose frequencies sensitive crystal strain due bending motion cantilever. A quantitative analysis shows good is obtained if magnetic-field gradient applied across during...
Rare-earth-doped crystals have numerous applications ranging from frequency metrology to quantum information processing. To fully benefit their exceptional coherence properties, the effect of mechanical strain on energy levels dopants---whether it is a resource or perturbation---needs be considered. We demonstrate that by applying uniaxial stress rare-earth-doped crystal containing spectral hole, we can shift hole controlled amount larger than width hole. deduce sensitivity...
We investigate the frequency response of narrow spectral holes in a doped crystal structure as function temperature below 1 K. identify particular regime which this significantly deviates from expected two-phonon Raman scattering theory. Namely, near 290 mK, we observed behavior exhibiting temperature-dependent shift zero to first order. This is interest for applications that require high stability, such laser stabilization, by operating scheme at specific point would result hole being...
The prospect of building a quantum information processor underlies many recent advances ion trap fabrication techniques. Potentially, computer could be constructed from large array interconnected traps. We report on micrometer-scale trap, fabricated bulk silicon using micro-electromechanical systems (MEMS) geometry is relatively simple in that the electrodes lie single plane beneath ions. In such we confine laser-cooled 24Mg+ ions approximately 40 microns above surface. technique and planar...
We present an experimental technique for realizing a specific absorption spectral pattern in rare-earth-doped crystal at cryogenic temperatures. This is subsequently probed on two channels simultaneously, thereby producing error signal allowing frequency locking of laser the said pattern. Appropriate combination leads to substantial reduction detection noise, paving way ultra-stable which noise can be made arbitrarily low when using multiple channels. use this realize with instability $ 1.7...
We report an experiment measuring simultaneously the temperatureand flux of ions produced by a cloud triplet metastablehelium atoms at Bose-Einstein critical temperature. The onsetof condensation is revealed sharp increase ion fluxduring evaporative cooling. Combining our measurements withprevious ionization in pure BEC,we extract improved value scattering length$a=11.3^{+2}_{-1}$ nm. analysis includes corrections takinginto accountthe effect atomic interactions on criticaltemperature, and...
Low phase noise microwave signals can be generated by photo-detecting the pulse train of an optical frequency comb locked to a high spectral purity continuous-wave reference. Amplitude-to-phase conversion is, however, well-known limitation this technique. Great care is usually required overcome constraint due its strong dependence on impinging power. Here we demonstrate combined use "magic point" operating conditions photodetectors, repetition rate multipliers, and coherent addition realize...
We have studied ionizing collisions in a BEC of metastable He. Measurements the ion production rate combined with measurements density and number atoms for same sample allow us to estimate both two- three-body contributions this rate. A comparison decay atom indicates that are largely or wholly responsible loss. Quantum depletion makes substantial correction constant.
We briefly discuss recent experiments on quantum information processing using trapped ions at NIST. A central theme of this work has been to increase our capabilities in terms computing protocols, but we have also applied the same concepts improved metrology, particularly area frequency standards and atomic clocks. Such may eventually shed light more fundamental issues, such as measurement problem.
We evidence the influence of surface effects for InAs quantum dots embedded into GaAs photonic nanowires used as efficient single photon sources. observe a continuous temporal drift emission energy that is an obstacle to resonant optics experiments at level. attribute sticking oxygen molecules onto wire, which modifies charge and hence electric field seen by dot. The temperature excitation laser power on this phenomenon studied. Most importantly, we demonstrate proper treatment nanowire...