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Phenomenological theory of bistability in polariton diodes

September 4th, 2010

Daniele Bajoni, Elizaveta Semenova, Aristide Lemaitre, Sylvain Barbay, Robert Kuszelewicz et al.
Polariton diodes have been recently shown to exhibit pronounced bistability induced by the control of the light-matter coupling via an external bias and optical pumping [D. Bajoni, E. Semenova, A. Lemaitre, S. Bouchoule, E. Wertz, P. Senellart, S. Barbay, R. Kuszelewicz, and J. Bloch, Phys. Rev. Let … [Appl. Phys. Lett. 97, 091107 (2010)] published Thu Sep 2, 2010.

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Light-hole and heavy-hole transitions for high-temperature long-wavelength infrared detection

September 4th, 2010

Y. F. Lao, P. K. D. D. P. Pitigala, A. G. U. Perera, H. C. Liu, M. Buchanan et al.
Hole transitions from the heavy-hole (hh) to the light-hole (lh) band contributing to the 410 [mu]m response range are reported on p-GaAs/AlGaAs detectors. The detectors show a spectral response up to 16.5 [mu]m, operating up to a temperature of 330 K where the lh-hh response is superimposed on th … [Appl. Phys. Lett. 97, 091104 (2010)] published Thu Sep 2, 2010.

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Substrate-induced bianisotropy in metamaterials

September 4th, 2010

David A. Powell and Yuri S. Kivshar
We demonstrate that the presence of a supporting substrate can break the symmetry of a metamaterial structure, changing the symmetry of its effective parameters, and giving rise to bianisotropy. This indicates that magnetoelectric coupling will occur in all metamaterials fabricated on a substrate, i … [Appl. Phys. Lett. 97, 091106 (2010)] published Thu Sep 2, 2010.

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Coulomb effect inhibiting spontaneous emission in charged quantum dot

September 4th, 2010

Kamil Gradkowski, Tomasz J. Ochalski, Nicola Pavarelli, David P. Williams, Guillaume Huyet et al.
We investigate the emission dynamics of InAs/GaAs quantum dots (QDs) coupled to an InGaAs quantum well in a tunnel injection scheme by means of time-resolved photoluminescence. Under high-power excitation we observe a redshift in the QD emission of the order of 20 meV. The optical transition intensi … [Appl. Phys. Lett. 97, 091105 (2010)] published Thu Sep 2, 2010.

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The effect of mode spacing on the speed of quantum-well microcavity lasers

September 4th, 2010

C. H. Wu, F. Tan, M. Feng, and N. Holonyak, Jr.
Oxide-confined quantum-well microcavity vertical-cavity surface-emitting lasers (VCSELs) of three-diameters (aperture size d~2, 2.5, and 3.5 [mu]m) have been fabricated that operate as nearly single-mode lasers at ultralow thresholds I=0.15, 0.16, and 0.20 mA. Relative spectral intensities are meas … [Appl. Phys. Lett. 97, 091103 (2010)] published Wed Sep 1, 2010.

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A frequency-addressed plasmonic switch based on dual-frequency liquid crystals

September 4th, 2010

Yan Jun Liu, Qingzhen Hao, Joseph S. T. Smalley, Justin Liou, Iam Choon Khoo et al.
A frequency-addressed plasmonic switch was demonstrated by embedding a uniform gold nanodisk array into dual-frequency liquid crystals (DFLCs). The optical properties of the hybrid system were characterized by extinction spectra of localized surface plasmon resonances (LSPRs). The LSPR peak was tune … [Appl. Phys. Lett. 97, 091101 (2010)] published Mon Aug 30, 2010.

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Surface plasmon enhanced responsivity in a waveguided germanium metal-semiconductor-metal photodetector

September 4th, 2010

Fang-Fang Ren, Kah-Wee Ang, Junfeng Song, Qing Fang, Mingbin Yu et al.
The authors report on high transverse magnetic (TM)-mode responsivity in a waveguided germanium Schottky-barrier metal-semiconductor-metal photodetector on silicon-on-insulator substrate for operating wavelength at 1550 nm. The employed aluminum interdigitated electrodes act as a one-dimensional rec … [Appl. Phys. Lett. 97, 091102 (2010)] published Mon Aug 30, 2010.

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High performance continuum-to-continuum quantum cascade lasers with a broad gain bandwidth of over 400 cm

September 4th, 2010

Yu Yao, Xiaojun Wang, Jen-Yu Fan, and Claire F. Gmachl
A quantum cascade laser structure is demonstrated that provides a broadband gain spectrum of 430 cm with a peak emission wavelength around 4.8 [mu]m. The laser active region is based on multiple transitions from strongly coupled upper states to lower laser states. In spite of the broad gain spectr … [Appl. Phys. Lett. 97, 081115 (2010)] published Fri Aug 27, 2010.

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Tailoring light scattering of nanowires for photovoltaic applications

September 3rd, 2010

Controlling the dimensions of semiconductor nanowires influences the scattering and absorption of light, potentially leading to solar cells with reduced scattering or enhanced absorption.

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New Hubble observations of Supernova 1987A reveal composition of “star guts” pouring out

September 2nd, 2010

The new observations of the “String of Pearls” surrounding the remnant not only tell scientists what elements are being recycled into the Large Magellanic Cloud, but also how the dwarf galaxy changes its environment on human timescales.

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