EQEC'96. 1996 European Quantum Electronic Conference最新文献_第8页

Resonance fluoresceuce Of an Atom Equally Perturbed by Light and Collisions. 受光和碰撞等扰动的原子的共振荧光。

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561811

W. Chalupezak, W. Gawlik, B. Lobodzinski, T. Pałasz, J. Zachorowski

引用次数: 0

New Experiments with Optical Lattices 光学晶格的新实验

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561509

A. Hemmericl, A. Gorlitz, M. Weidemuller, T. Hansch

{"title":"New Experiments with Optical Lattices","authors":"A. Hemmericl, A. Gorlitz, M. Weidemuller, T. Hansch","doi":"10.1109/EQEC.1996.561509","DOIUrl":"https://doi.org/10.1109/EQEC.1996.561509","url":null,"abstract":"rly ~II~II~IIIII ~ . l twry of dectrical coi~drirtivity iii crystal latticcs hy I3loch aiid Zener [ I ] I(YI t,o the striking predirtion that a lioniogciicons static clcctric ficld iiiduces ail oscillatory rather thau u~ i i fo r~ r i notion of the electrons. l lcrr wc preseut Blocli oscillations o f atoiiis i i i I.he fundanieutal and iii the first excit.ccl cwxgy baiid of a periodic optical potential 121. ‘lliis poteiitial results from the light-shift of the grouud state of atoms illuminatr t l hy a laser stailding wave. The laser is detuncd far from any atomic resouancc so tliat spoiitancoiis emission can he neglected. Using one-dimensional Ranian laser cooling [3,4] we first prepare a gas of free atoms with a ~nomentum spread 61, = hk/4 in the direction of the standing wave, where hk i s tlic pliol.on ~nonrei~tum. The corresponding atomic coherence length h/6p extends over ~everal periods d = X/2 = 7 r / k of the optical lattice. I3y adiabatically switching on thc light potential this initial momentum distribution is turned into a statistical mixture of 131ocli stales i n the ground energy band with a quasi-rnomnrtu~n width 6y = 6 p / h much snrallcithan the width 2k of the Brillouin zone. We mimic a constant external force by inl.roducing a t.uiiable frequency difference 6 v ( t ) between the two counterpropagating laser waves rreal.ing the optical potential. For a linear variation io time of 6v( l ) a constant inerl.ial force 1.’ = m a = -mX$6v( t ) /2 is exerted 011 the atoms in the frame of the slanding wave. After a given evolution time, we abruptly switch off the light potential and inrasure thr momentum distribution of the Blocli sl.ate with a resolution of R k / l S . ‘I’lie nieaii atomic velocity displays oscillations with periods in the millisecond range and a~nplit~ndes between 0.7 and 0.3 UR for potential depths (io between 0.8 and 5.6 ER. where i>f? = h.k/7n is the recoil velocity and ER = (hk)’/2m the recoil energy. We measured positive and negative effective masses, differeut from the mass of the free cesium atom. Froiu the measured velocity curves we can reconstruct the shape of the fundamental energy band. Wr have also calculated numerically the band structure for our experimental values of [ io. The agreement with the experimental data is quite good. 4k have niadc investigations of atom acceleratiori in (.he case of deeper potentials up to r:, = 10EJ3. We could still observe Bloch states after more thau 40 oscillation periods. 111 t.lrc Iaboralory frame, this corresponds to a coherent mom en tun^ transfer of S O U . prodnring aii atomic beam with subrecoil momentum spread (h1;/4) in the beam direction.","PeriodicalId":11780,"journal":{"name":"EQEC'96. 1996 European Quantum Electronic Conference","volume":"35 1","pages":"5-5"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86977735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum Coding and Quantum Communications 量子编码与量子通信

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561539

M. Reck, Klaus Mattle, H. Weinfurter, A. Zeilinger, P. G. Kwait

引用次数: 0

Cryogenic Optical Resonators For Ultra-Stable Lasers 超稳定激光器的低温光学谐振器

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561579

S. Seel, R. Storz, G. Ruoso, S. Schiller, J. Mlynek

引用次数: 0

Generation of Quadrature Squeezed Light By Cross-Phase Modulation in Semiconductors 半导体中交叉相位调制产生正交压缩光

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561521

G. von Plessen, A. M. Fox, M. Dabbicco, G. Schucan, J. F. Ryan

引用次数: 0

Non Linear Spectroscopy of Single Molecules in Low Temperature Solids 低温固体中单分子的非线性光谱研究

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561791

B. Lounis, P. Tamarat, M. Orrit

{"title":"Non Linear Spectroscopy of Single Molecules in Low Temperature Solids","authors":"B. Lounis, P. Tamarat, M. Orrit","doi":"10.1109/EQEC.1996.561791","DOIUrl":"https://doi.org/10.1109/EQEC.1996.561791","url":null,"abstract":"The fluorescence exciliition spectra ol small and dilute samples of solid solutions kept at helium temperatures display sharp homogeneous lines of individual solute molecules. Single molecule lines arc sensitive to external perturbations such as electric fields or pressurc. The fluctuations of the fluorescence signal show characteristic times ranging from nanoseconds to minutes. They give information about the dynamics within the molecule (intersystem crossing, Rabi nutation) as well i ~ s in the surrounding matrix (spectral diffusion of the resonance frequency). Non-linear optical experiments have been performed on single molecules. First, single pentacene molecules in p-terphenyl crystals demonstrate paramagnetic resonance in their triplet states. This non-linear efrect appears when the molecule is subjected to resonant microwaves in addition to optical excitation. Microwave pulses were used to produce transient effects, and were synchronised with the molecule itself. We performed non-linear optical experiments of the pump-probe type on the narrow excitation lines of single terrylene molecules in a pterphenyl crystal. At low saturations, the pump beam was found to shift the optical transition of the molecule as expected : proportionally to the intensity and inverse pump detuning. The variations of the fluorescence signal (proportional to the excited state population of the molecule) were also studied with pump and probe closer to resonance. Because of triplet saturation, the signal variations are rather weak and high pump powers had to be used. Upon tuning the probe beam through the resonance, W-shaped structures were obtaiped, recalling Autler-Townes splittings. The shape of the structures is correctly reproduced by numerical simulations of the optical Bloch equations in two intense laser fields and indicates photon exchange between pump and probe beams. These results show the possibility of non-linear and quantum optical experiments on single molecules in condensed matter, even though thc shifts observed are much weaker than disorder-induced inhomogeneous broadening. I 09:oo QThE32 Q U A N T U M EFFEC'TS A N D SPECTRAL DYNAMICS OF SINGLE TEIlRYLENE MOLECULES I N A /+TERPHENYL CRYSTAL.","PeriodicalId":11780,"journal":{"name":"EQEC'96. 1996 European Quantum Electronic Conference","volume":"35 1","pages":"160-160"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89231475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-Plasmon Processes in Spectroscopy of Electron-Hole Plasma in A2B6 Semiconductors A2B6半导体中电子-空穴等离子体光谱中的多等离子体过程

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561548

V. S. Vavilov, A. Klyukanov, K. Sushkevich, M. Chukichev, A. Awawdeh, R. R. Resvanov

引用次数: 0

Superradiant Excitons in GaAs Single Quantum Wells GaAs单量子阱中的超辐射激子

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561530

P. Vledder, F. Schuurmans, J. I. Dijkhuis

引用次数: 0

Emission of Terahertz Radiation From Optically Excited Coherent Plasmons in a Two-Dimensional Electron Gas 二维电子气体中光激发相干等离子体的太赫兹辐射发射

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561594

M. Vosseburger, H. Roskos, F. Wolter, C. Waschke, K. Kurz, K. Hirakawa, I. Wilke, K. Yamanaka

引用次数: 0

A New Mechanism of Passive Mode Locking in A Soliton Fiber Laser 一种新的孤子光纤激光器无源锁模机制

EQEC'96. 1996 European Quantum Electronic Conference Pub Date : 1996-01-01 DOI: 10.1109/EQEC.1996.561942

V. Bryksin, M. Petrov

{"title":"A New Mechanism of Passive Mode Locking in A Soliton Fiber Laser","authors":"V. Bryksin, M. Petrov","doi":"10.1109/EQEC.1996.561942","DOIUrl":"https://doi.org/10.1109/EQEC.1996.561942","url":null,"abstract":"The propagation of pulses and beam profiles under the action of two-photon absorption (TPA) has great interest nowadays, because the potential action of TPA as a limitation factor in switching devices using high nonlinearitiesll]. Variational approaches have been applied successfully to the problem of temporal dispersion andlor spatial diffraction in nonlinear propagation which is described by a nonlinear Schrodinger equation[2]. These approaches am usually limited to conservative optical systems, due to mathematical difficulties that the dissipation term brings about. The purpose of this study is lo apply a variational technique to investigate dissipative nonlinear propagation. By means of the generalization of the Kantorovich method, suitable for non-conservative systems, we are able to deal with the problem of soliton propagation under the influence of TPA. Based on the characteristics of the exact solution in the absence of TPA. and supposing an adiabatic process we propose a family of soliton solutions as trial functions. This procedure results in analytical expressions that illustrate the changes during propagation of the soliton’s parameters such as amplitude, width and phase. The rate at which energy is dissipated is also obtained and, as expected, from a TPA process. is proportional to 1’. Comparison of the behavior predicted by our approximate solutions with numerical results available in the literature show very good agreement[3]. The dissipative variational approach can be extended to deal with more dimensions in the NLSE and to different kinds of dissipative nonlinearities as €?+-doped fiber amplifiers. In conclusion, a variational approach for non-conservative propagation has been used to provide a suggestive description for soliton propagation under TPA effect. As the problem of non-conservative propagation is shared by many areas of physics other than light pulse propagation, we emphasize that the present approach may be useful for a quite wide range of areas and different kinds of dissipative terms.","PeriodicalId":11780,"journal":{"name":"EQEC'96. 1996 European Quantum Electronic Conference","volume":"20 1","pages":"241-241"},"PeriodicalIF":0.0,"publicationDate":"1996-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74994026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0