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Quantum Electronics and Laser Science Conference, 2002. QELS '02. Technical Digest. Summaries of Papers Presented at the

Date 19-24 May 2002

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  • Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Conference Edition (IEEE Cat. No.02CH37338)

    Publication Year: 2002
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    Freely Available from IEEE
  • Lasing in disordered media

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (126 KB) | HTML iconHTML

    Summary form only given. We developed a theoretical model for random lasers based on the eigenmodes of a random medium. Lasing with non-resonant feedback corresponds to lasing in a set of coupled eigenmodes, while lasing with resonant feedback corresponds to lasing in individual eigenmodes. We derived the dependence of the lasing threshold pump intensity on the transport mean free path, the pump a... View full abstract»

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  • Bandgap enhanced random laser

    Publication Year: 2002, Page(s):1 - 2
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (229 KB) | HTML iconHTML

    Summary form only given. A laser made of such disordered medium is called a random laser. This is in contrast to commercially available compound semiconductor lasers made of single crystalline films. Recently we observed random laser action with coherent feedback in ZnO powder and polycrystalline films. This opens the possibility of utilizing disordered semiconductor microstructures as alternative... View full abstract»

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  • Temperature control of laser action in scattering media

    Publication Year: 2002, Page(s):2 - 3
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (208 KB) | HTML iconHTML

    Summary form only given. Our system is comprised of hydroxypropyl cellulose (HPC) with a nominal average molecular weight of 370,000 dissolved in deionized water. HPC is a FDA-approved, nonionic, water-soluble cellulose derivative possessing lower critical soluble temperature (LCST) in water. When a laser dye with high gain is dissolved into this system, it makes a nice random laser system where s... View full abstract»

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  • Random laser without diffusion?

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (104 KB) | HTML iconHTML

    Summary form only given. The sample (scattering Nd/sub 0.5/La/sub 0.5/Al/sub 3/(BO/sub 3/)/sub 4/ ceramic) was excited at 532 nm with a 10 ns laser pulses. The stimulated emission was characterized by a distinctive threshold. The threshold energy E/sub th/ was linearly proportional to the diameter of the pumped spot in a very broad range. View full abstract»

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  • Direct evidence for stationary light

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (107 KB) | HTML iconHTML

    Summary form only given. In recent years there have been several reports of pulsed laser action in random media, including powdered semi-conductors, polymers, rare earth and transition-metal-doped powders. These results were ascribed in a few cases to strong Anderson localization, despite the fact that distance scales of the virtual cavities associated with these lasers were much greater than a wa... View full abstract»

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  • Excitation of localized modes in active random media

    Publication Year: 2002, Page(s):4 - 5
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (203 KB) | HTML iconHTML

    Summary form only given. Lasing in strongly scattering media with resonant feedback has recently been reported. In this work, we discuss the interplay of Anderson localization and laser action in active random media. The system is a two-dimensional medium made of circular scatterers imbedded in an active matrix. We have used a numerical model, which solves simultaneously the Maxwell's equations an... View full abstract»

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  • Deterministic ion-photon interaction in a cavity

    Publication Year: 2002, Page(s):5 - 6
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (113 KB) | HTML iconHTML

    Summary form only given. In a recent experiment, we have investigated the interaction between a single /sup 40/Ca/sup +/-ion stored in a radio-frequency trap and the field of an optical cavity. One mode of the cavity was tuned to the S/sub 1/2/ to P/sub 1/2/ transition of singly ionized calcium at a wavelength of /spl lambda/ = 397 nm. Using laser Doppler cooling in conjunction with the strong con... View full abstract»

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  • Control and information with conditional quantum measurements

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (209 KB) | HTML iconHTML

    Summary form only given. Conditional quantum measurements allow the observation of quantum fluctuations which result from a measurement on a quantum system. These dynamics are characterized with time-ordered correlation functions. Control and observation of these dynamics presents a challenging new direction in cavity QED from both the technological and theoretical point of view. Wiseman has consi... View full abstract»

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  • Cavity accelerated superradiant systems and optical pulse area transitors

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (114 KB) | HTML iconHTML

    Summary form only given. The radiative behavior of an ensemble of correlated atoms can be dramatically different from that of a single atom. Correlation, for example, can give rise to sub- or superradiant emission. Experimental studies of the fascinating correlative effects expected have been severely constrained by difficulties in creating suitably correlated media and by propagation effects that... View full abstract»

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  • Multiple thresholds and many-atom dynamics in the cavity QED microlaser

    Publication Year: 2002, Page(s):6 - 7
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (210 KB) | HTML iconHTML

    Summary form only given. The cavity QED microlaser is a laser based on the ideal model of atoms undergoing well-defined interaction with a single mode of an optical cavity. It is the optical analogue of the micromaser. Due to the coherent nature of the atom-cavity interaction, the microlaser exhibits behavior foreign to conventional lasers. View full abstract»

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  • Dynamic modification of the conditional evolution of a cavity QED system

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (117 KB) | HTML iconHTML

    Summary form only given. We have developed a technique which combines the state preparation intrinsic to the g/sup (2)/ (/spl tau/) measurement with the external control of an intensity-step. We detect a first photon and before the system can oscillate back to steady state-which typically occurs in < 100 ns-the intensity of the system drive is changed. View full abstract»

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  • Weak values, quantum trajectories, and the Stony-Brook cavity QED experiment

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (117 KB) | HTML iconHTML

    Summary form only given. I apply quantum trajectory theory to the recent Stony-Brook cavity QED experiment demonstrating waveparticle duality. I show that the left half of the fractional correlation function he measured in that experiment can be recast as a dynamical weak value. The system consists of a damped cavity, very weakly driven, through which a beam of resonant atoms pass. The weak measur... View full abstract»

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  • Strong nonlinear coherent effects in a single semiconductor quantum dot

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (104 KB) | HTML iconHTML

    Summary form only given. The optical properties of semiconductor quantum dots have been studied intensively in the past few years. Recently the experiment has demonstrated not only the ability to probe a single QD but also how to coherently control the exciton in a single QD on a time scale that is short compared with the decoherence time. We had proposed a scheme to use the excitons in QD as qubi... View full abstract»

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  • Quantum coherence in a coupled exciton-quantum-dot system

    Publication Year: 2002, Page(s):8 - 9
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (186 KB) | HTML iconHTML

    Summary form only given. Optically driven semiconductor quantum dots (QD's) are of interest in many areas of opto-electronic devices as well as featuring prominently in many proposals for quantum computing. The necessary component of a scalable quantum computer, the two-qubit logic gate, requires two separate yet interacting qubits. In QD's, this is a multi-exciton state. Recently the bound state ... View full abstract»

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  • Characteristics of relaxation process in an optically coupled quantum-dots system

    Publication Year: 2002, Page(s):9 - 10
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (199 KB) | HTML iconHTML

    Summary form only given. Optical near-field techniques are considered promising as enabling technologies for fabrication and high-speed operation of novel optical devices in nanometric regime, because of the size-dependent localization far beyond the diffraction limit of light. We have regarded the optical near field as a coupled mode of photons and matter excitation, i.e., polaritons, and derived... View full abstract»

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  • Optical spectroscopy of single trions

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (117 KB) | HTML iconHTML

    Summary form only given. We observed distinctive signatures in the magneto-optical fine structure spectra of singly charged and uncharged QDs. We show that in the absence of a magnetic field the photoluminescence spectrum is characterized by two predominant transitions that we identify as exciton and trion singlet recombination transitions. As the temperature is increased several lines rapidly dec... View full abstract»

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  • Entangled exciton states in quantum dot molecules

    Publication Year: 2002, Page(s):10 - 11
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (210 KB) | HTML iconHTML

    Summary form only given. We present spectroscopic studies of single self-assembled InAs/GaAs quantum dot molecules that support the feasibility of creating an optically driven quantum gate. The evolution of the excitonic recombination spectrum with varying separation between the dots allows us to demonstrate coherent tunneling of carriers across the separating barrier and the formation of entangle... View full abstract»

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  • Transient nonlinear spectroscopy of biexcitons in single quantum dots

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (110 KB) | HTML iconHTML

    Summary form only given. We report the first transient differential transmission (DT) spectroscopy of biexcitons in single quantum dots. Quantum dots were formed by interface fluctuations in a thin GaAs layer are probed through submicron apertures on the sample surface. View full abstract»

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  • Microwave transmission through metamaterials in free space

    Publication Year: 2002
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (116 KB) | HTML iconHTML

    Summary form only given. In order to investigate properties of metamaterials, we constructed a composite structures which consists of periodical arrangement of thin copper wires and SRRs on a circuit board We first measured the transmission spectra of the thin wire and SRR mediums individually. The measurements are performed in free space by using a HP 8510C network analyzer and microwave horn ant... View full abstract»

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  • Chiral gratings-a new class of polarization sensitive metamaterials

    Publication Year: 2002, Page(s):12 - 13
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (241 KB) | HTML iconHTML

    Summary form only given. Metallic bilayered structures with chirality and inductive coupling are predicted to show huge optical polarization rotatory power resembling that of liquid crystals. The semi-chiral planar gratings described here belong to a distinctively different class of 2D structures known as planar chiral structures. View full abstract»

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  • Optical elements based on space-variant Pancharatnam-Berry phase manipulation

    Publication Year: 2002, Page(s):13 - 14
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (225 KB) | HTML iconHTML

    Summary form only given. We demonstrate novel optical phase elements based on the space-domain Pancharatnam-Berry phase. Unlike diffractive and refractive elements, the phase is not introduced through optical path differences, but results from the geometrical phase that accompanies space variant polarization manipulation. We analyze Pancharatnam-Berry phase optical elements (PBOEs) that consist of... View full abstract»

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  • Photo-induced gyrotropic effects in semiconductor microcavities

    Publication Year: 2002, Page(s):14 - 15
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (181 KB) | HTML iconHTML

    Summary form only given. We assess the gyrotropic part of these photo-induced changes through a theoretical and experimental study of the polarization effects occurring at high exciton densities in a microcavity operated in the strong coupling regime. In this nonlinear process, a circularly-polarized pump pulse induces polarization changes on a linearly polarized incident probe beam due to the hug... View full abstract»

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  • State engineering in multi-atom systems: from spin squeezing to quantum information processing

    Publication Year: 2002
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (99 KB) | HTML iconHTML

    Summary form only given. Methods to prepare multi-particle entangled states of atoms and to entangle the collective degrees of freedom of separate systems each containing many atoms are presented. The use of entanglement in high-precision measurements and in continuous variable quantum information are discussed and the status of experiments will be reviewed. View full abstract»

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  • Long-lived spin state of an atomic gas-a storage medium for a quantum state of light

    Publication Year: 2002, Page(s):15 - 16
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (190 KB) | HTML iconHTML

    Summary form only given. The spin polarized ground state of a cesium gas in a paraffin coated glass cell at room temperature has been recently used for generation of a long lived entangled state of atoms. In this paper we report on the first results towards using this medium as a quantum memory for polarization states of a light beam. The possibility of a reversible transfer of polarization states... View full abstract»

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