Article

Record Performance of Electrical Injection Sub-wavelength Metallic-Cavity Semiconductor Lasers at Room Temperature

Optics Express (Impact Factor: 3.53). 02/2013; 21(4):4728-4733. DOI: 10.1364/OE.21.004728
Source: PubMed

ABSTRACT We demonstrate a continuous wave (CW) sub-wavelength metallic-cavity semiconductor laser with electrical injection at room temperature (RT). Our metal-cavity laser with a cavity volume of 0.67λ3 (λ = 1591 nm) shows a linewidth of 0.5 nm at RT, which corresponds to a Q-value of 3182 compared to 235 of the cavity Q, the highest Q under lasing condition for RT CW operation of any sub-wavelength metallic-cavity laser. Such record performance provides convincing evidences of the feasibility of RT CW sub-wavelength metallic-cavity lasers, thus opening a wide range of practical possibilities of novel nanophotonic devices based on metal-semiconductor structures.

Download full-text

Full-text

Available from: P.J. van Veldhoven, Jun 25, 2015
0 Followers
 · 
127 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We perform two analyses on temperature effects in Metal-Clad Subwavelength Semiconductor Lasers (MCSELs). Firstly, we analyze the temperature dependence of the threshold gain in the infinite waveguide approximation. We show that the dielectric layer of the semiconductor-dielectric-metal composite waveguide (CWG) becomes increasingly important as temperature increases. However, we further show that the optimal geometry of the CWG is nearly invariant with the temperature. Secondly, we relax the infinite waveguide assumption with the fully 3D finite element method, and analyze the temperature dependence of the spontaneous emission factor, β. We identify a cavity geometry that mitigates detuning between the dominant cavity mode and emission spectra. Ignoring coupling to freespace modes, we explain that the modified cavity may lead to a MCSEL with large β (~0.5) for all temperatures.
    Proceedings of SPIE - The International Society for Optical Engineering 02/2014; DOI:10.1117/12.2055000 · 0.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Metallic cavities have been extensively studied to realize small-volume nanocavities and nanolasers. However cavity-resonance quality (Q) factors of nanolasers observed up to now remain low (up to ∼500) due to metal optical absorption. In this paper, we report the observation of highest Q factors of 9000 at low temperature and ∼6000 near room temperature in a metallic cavity with a probe of sub-bandgap emission of Si-doped GaAs. We analyze the temperature dependence of cavity-mode resonance wavelengths and show that the refractive-index term dominates the measured temperature dependence. We also show that this refractive-index term is cavity-mode dependent and the fitting procedure offers a new method to identify cavity modes. We simulate the metallic cavity with finite-element method and attribute the high-Q cavity mode to a whispering gallery optical mode. This mode is shown to have isotropic polarization dependence of the output emission, which is preferable for quantum information applications.
    Nanotechnology 02/2015; 26(8):085201. DOI:10.1088/0957-4484/26/8/085201 · 3.67 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We propose a novel subwavelength metallic InP/InGaAs laser with a capsule-shaped cavity. By introducing curved metallic facets at the both ends, resonant modes can be strongly confined inside the center of the cavity, which not only improves the confinement factor and the Q factor, but also reduces the cavity volume. As an example case, we numerically demonstrate that the proposed structure can decrease the plasmonic loss and improve the Q factor from 197 to 297 and reduce the threshold current from 291 to 60 µA with the effective modal volume of 0.45 µm3. In addition, we demonstrate that there exists an optimal structure of the capsule-shaped cavity to minimize the current threshold.
    Japanese Journal of Applied Physics 10/2014; 53(11):112703. DOI:10.7567/JJAP.53.112703 · 1.06 Impact Factor