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Cavity quantum electrodynamics, a central research field in optics and solid-state physics, addresses properties of atom-like emitters in cavities and can be divided into a weak and a strong coupling regime. For weak coupling, the spontaneous emission can be enhanced or reduced compared with its vacuum level by tuning discrete cavity modes in and out of(More)
We report time-resolved photoluminescence investigations of as-grown wurtzite InP nanowires ͑d av =16 nm͒ on a ͑111͒ silicon substrate as a function of emission energy, temperature, and excitation fluence. The observed luminescence transients are well described by a biexponential decay process, with ␶ fast ϳ 0.3– 0.7 ns and ␶ slow ϳ 2 – 5 ns, which does not(More)
—InAs quantum-dot (QD) lasers were investigated in the temperature range 20–300 K and under hydrostatic pressure in the range of 0–12 kbar at room temperature. The results indicate that Auger recombination is very important in 1.3-m QD lasers at room temperature and it is, therefore, the possible cause of the relatively low characteristic temperature(More)
Long-distance quantum teleportation and quantum repeater technologies require entanglement between a single matter quantum bit (qubit) and a telecommunications (telecom)-wavelength photonic qubit. Electron spins in III-V semiconductor quantum dots are among the matter qubits that allow for the fastest spin manipulation and photon emission, but entanglement(More)
We demonstrate coupling and entangling of quantum states in a pair of vertically aligned, self-assembled quantum dots by studying the emission of an interacting electron-hole pair (exciton) in a single dot molecule as a function of the separation between the dots. An interaction-induced energy splitting of the exciton is observed that exceeds 30(More)
Conventional semiconductor laser emission relies on stimulated emission of photons, which sets stringent requirements on the minimum amount of energy necessary for its operation. In comparison, exciton-polaritons in strongly coupled quantum well microcavities can undergo stimulated scattering that promises more energy-efficient generation of coherent light(More)
The heterogeneous integration of III-V optoelectronic devices with Si electronic circuits is highly desirable because it will enable many otherwise unattainable capabilities. However, direct growth of III-V thin film on silicon substrates has been very challenging because of large mismatches in lattice constants and thermal coefficients. Furthermore, the(More)
—One of the essential building-blocks of miniature pho-tonic crystal (PC)-based photonic integrated circuits (PICs) is the sharp bend. Our group has focused on the 2-D photonic crystal based on a triangular lattice of holes perforating a standard het-erostructure. The latter, GaAlAs-based or InP-based, is vertically a monomode waveguide. We consider(More)
Lasers are recognized for coherent light emission, the onset of which is reflected in a change in the photon statistics. For many years, attempts have been made to directly measure correlations in the individual photon emission events of semiconductor lasers. Previously, the temporal decay of these correlations below or at the lasing threshold was(More)
  • Oliver Paul, Christian Imhof, +7 authors Marco Rahm
  • 2009
We present a polarization-independent metamaterial design for the construction of electrically tunable terahertz (THz) devices. The implemented structure consists of an array of gold crosses fabricated on top of an n-doped gallium arsenide (GaAs) layer. Utilizing THz time-domain spectroscopy, we show that the electric resonance and thus the transmission(More)