Jean Hare | UPMC Sorbonne Universités (original) (raw)
Papers by Jean Hare
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2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011
ABSTRACT The author presents the significant improvement on lowest laser threshold for a rare-ear... more ABSTRACT The author presents the significant improvement on lowest laser threshold for a rare-earth based microlaser from the previous work of Sandoghdar et. al (1996), achieving values down to 40 nW. Beside the unique properties of whispering gallery mode (WGM) silica microcavities, this progress relies on the use of lanthanide oxide nanoparticles (NP) for their functionalization. It also takes advantage of some techniques that the authors have recently introduced.
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Optics Letters, 1994
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EQEC 96 1996 European Quantum Electronic Conference EQEC-96, 1996
ABSTRACT In our experiment Nd3+ ions are pumped with a diode laser at 807nm using a resonant WG m... more ABSTRACT In our experiment Nd3+ ions are pumped with a diode laser at 807nm using a resonant WG mode. The coupling to this mode is achieved via frustrated total internal reflection using a high index prism. The emission from the ions is then coupled out via the Same prism and is diagnosed using a spectrometer and a Fabry-Perot. The figure shows a lasing threshold of about 200nW in a sphere with a diameter of 56μm, a doping level of about O.l%, and at a cold cavity Q of 2x108. Furthermore, the evanescent wave coupling allows us to investigate the microlaser action over a cold cavity Q range of more than one order of magnitude by varying the sphere-prism distance. We discuss future experiments with lower doping levels and at cryogenic temperatures aimed at the reduction of the homogeneous linewidth. Such an approach could lead to the laser action from a single ion permanently trapped in a solid medium.
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Optoelectronic Integrated Circuits VII, 2005
ABSTRACT We report an experiment where InAs/GaAs self-organized Quantum Dots (QD) are coupled to ... more ABSTRACT We report an experiment where InAs/GaAs self-organized Quantum Dots (QD) are coupled to the evanescent field of very-high-Q Whispering Gallery Modes (WGM) in a silica microsphere. The high performance of these microcavity and nanoemitters allowed to achieve very low threshold (200 &mum) laser operation at room temperature, involving a few thousands of QD. We show that such a low threshold relies heavily on WGM deconfinement and reconstruction in the micromesa etched in GaAs sample. Next, we present some prospects on further experiments involving various semiconductor nanostructures coupled to microspheres or to silica microtoroids integrated on a Si chip (as recently introduced by K.J.~Vahala and coworkers at Caltech).
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2011 13th International Conference on Transparent Optical Networks, 2011
ABSTRACT We report on several enhancements in silica microcavities fabrication, characterization ... more ABSTRACT We report on several enhancements in silica microcavities fabrication, characterization and functionalization. A special emphasis is put on mode identification, which gives access to the fundamental mode in both microspheres and microtoroids and to functionalization by nanoemitters, which open the way to original low threshold lasers. A record value of a threshold of 40 nW has been demonstrated for a microsphere doped with rare-earth oxide nanoparticles.
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New Journal of Physics, 2001
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Ultrathin magnetic cobalt-based Au/Co/Au trilayers have been studied by the optical second harmon... more Ultrathin magnetic cobalt-based Au/Co/Au trilayers have been studied by the optical second harmonic generation (SHG) and by the linear magneto-optical Kerr effect (MOKE). We show that SHG has a selective interface and surface sensitivity, whereas MOKE is bulk-sensitive. SHG was used to probe the surface plasmon resonance in Au/Co/Au films. The resonant coupling of surface plasmons with SHG, results in an enhancement and sign reversal of nonlinear magneto-optical effects. Model calculations of the observed phenomena are given on the basis of a nonlocal field theory, which permits to distinguish the different interface contributions to SHG.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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Advanced Series in Applied Physics, 1996
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Silica microspheres behave as efficient optical microresonators when small-volume whispering-gall... more Silica microspheres behave as efficient optical microresonators when small-volume whispering-gallery modes (WGMs) are used. We have realized a cryogenic set-up to work with microspheres immersed in a superfluid helium bath. Quality factors up to 109 have been obtained at 2 K. In this environment, we have been able to observe a dispersive bistable behavior of the WGM resonances, due to
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Physical Review Letters, 1988
ABSTRACT Circular atoms, i.e., Rydberg atoms with maximum angular momentum, are semiclassical ato... more ABSTRACT Circular atoms, i.e., Rydberg atoms with maximum angular momentum, are semiclassical atoms of great interest for Rydberg constant metrology and QED tests. Following a suggestion by Delande and Gay, we have prepared circular atoms by a new method, involving the adiabatic switching of crossed electric and magnetic fields. The method demonstrated in Rydberg states of lithium (principal quantum number n=20 to 25) applies in a wide variety of experimental conditions.
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Bookmarks Related papers MentionsView impact
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2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011
ABSTRACT The author presents the significant improvement on lowest laser threshold for a rare-ear... more ABSTRACT The author presents the significant improvement on lowest laser threshold for a rare-earth based microlaser from the previous work of Sandoghdar et. al (1996), achieving values down to 40 nW. Beside the unique properties of whispering gallery mode (WGM) silica microcavities, this progress relies on the use of lanthanide oxide nanoparticles (NP) for their functionalization. It also takes advantage of some techniques that the authors have recently introduced.
Bookmarks Related papers MentionsView impact
Optics Letters, 1994
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EQEC 96 1996 European Quantum Electronic Conference EQEC-96, 1996
ABSTRACT In our experiment Nd3+ ions are pumped with a diode laser at 807nm using a resonant WG m... more ABSTRACT In our experiment Nd3+ ions are pumped with a diode laser at 807nm using a resonant WG mode. The coupling to this mode is achieved via frustrated total internal reflection using a high index prism. The emission from the ions is then coupled out via the Same prism and is diagnosed using a spectrometer and a Fabry-Perot. The figure shows a lasing threshold of about 200nW in a sphere with a diameter of 56μm, a doping level of about O.l%, and at a cold cavity Q of 2x108. Furthermore, the evanescent wave coupling allows us to investigate the microlaser action over a cold cavity Q range of more than one order of magnitude by varying the sphere-prism distance. We discuss future experiments with lower doping levels and at cryogenic temperatures aimed at the reduction of the homogeneous linewidth. Such an approach could lead to the laser action from a single ion permanently trapped in a solid medium.
Bookmarks Related papers MentionsView impact
Optoelectronic Integrated Circuits VII, 2005
ABSTRACT We report an experiment where InAs/GaAs self-organized Quantum Dots (QD) are coupled to ... more ABSTRACT We report an experiment where InAs/GaAs self-organized Quantum Dots (QD) are coupled to the evanescent field of very-high-Q Whispering Gallery Modes (WGM) in a silica microsphere. The high performance of these microcavity and nanoemitters allowed to achieve very low threshold (200 &mum) laser operation at room temperature, involving a few thousands of QD. We show that such a low threshold relies heavily on WGM deconfinement and reconstruction in the micromesa etched in GaAs sample. Next, we present some prospects on further experiments involving various semiconductor nanostructures coupled to microspheres or to silica microtoroids integrated on a Si chip (as recently introduced by K.J.~Vahala and coworkers at Caltech).
Bookmarks Related papers MentionsView impact
2011 13th International Conference on Transparent Optical Networks, 2011
ABSTRACT We report on several enhancements in silica microcavities fabrication, characterization ... more ABSTRACT We report on several enhancements in silica microcavities fabrication, characterization and functionalization. A special emphasis is put on mode identification, which gives access to the fundamental mode in both microspheres and microtoroids and to functionalization by nanoemitters, which open the way to original low threshold lasers. A record value of a threshold of 40 nW has been demonstrated for a microsphere doped with rare-earth oxide nanoparticles.
Bookmarks Related papers MentionsView impact
New Journal of Physics, 2001
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Ultrathin magnetic cobalt-based Au/Co/Au trilayers have been studied by the optical second harmon... more Ultrathin magnetic cobalt-based Au/Co/Au trilayers have been studied by the optical second harmonic generation (SHG) and by the linear magneto-optical Kerr effect (MOKE). We show that SHG has a selective interface and surface sensitivity, whereas MOKE is bulk-sensitive. SHG was used to probe the surface plasmon resonance in Au/Co/Au films. The resonant coupling of surface plasmons with SHG, results in an enhancement and sign reversal of nonlinear magneto-optical effects. Model calculations of the observed phenomena are given on the basis of a nonlocal field theory, which permits to distinguish the different interface contributions to SHG.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Advanced Series in Applied Physics, 1996
Bookmarks Related papers MentionsView impact
Silica microspheres behave as efficient optical microresonators when small-volume whispering-gall... more Silica microspheres behave as efficient optical microresonators when small-volume whispering-gallery modes (WGMs) are used. We have realized a cryogenic set-up to work with microspheres immersed in a superfluid helium bath. Quality factors up to 109 have been obtained at 2 K. In this environment, we have been able to observe a dispersive bistable behavior of the WGM resonances, due to
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Physical Review Letters, 1988
ABSTRACT Circular atoms, i.e., Rydberg atoms with maximum angular momentum, are semiclassical ato... more ABSTRACT Circular atoms, i.e., Rydberg atoms with maximum angular momentum, are semiclassical atoms of great interest for Rydberg constant metrology and QED tests. Following a suggestion by Delande and Gay, we have prepared circular atoms by a new method, involving the adiabatic switching of crossed electric and magnetic fields. The method demonstrated in Rydberg states of lithium (principal quantum number n=20 to 25) applies in a wide variety of experimental conditions.
Bookmarks Related papers MentionsView impact