3 research outputs found
Strong Amplified Spontaneous Emission from High Quality GaAs<sub>1–<i>x</i></sub>Sb<sub><i>x</i></sub> Single Quantum Well Nanowires
Quantum
confinement in semiconductor nanowires is of contemporary
interest. Enhancing the quantum efficiency of quantum wells in nanowires
and minimizing intrinsic absorption are necessary for reducing the
threshold of nanowire lasers and are promising for wavelength tunable
emitters and detectors. Here, we report on growth and optimization
of GaAs<sub>1–<i>x</i></sub>Sb<sub><i>x</i></sub>/Al<sub>1–<i>y</i></sub>Ga<sub><i>y</i></sub>As quantum well heterostructures formed radially around pure
zinc blende GaAs core nanowires. The emitted photon energy from GaAs<sub>0.89</sub>Sb<sub>0.11</sub> quantum well (1.371 eV) is smaller than
the GaAs core, thus showing advantages over GaAs/Al<sub>1–<i>y</i></sub>Ga<sub><i>y</i></sub>As quantum well nanowires
in photon emission. The high optical quality quantum well (internal
quantum efficiency reaches as high as 90%) is carefully positioned
so that the quantum well coincides with the maximum of the transverse
electric (TE01) mode intensity profile. The obtained superior optical
performance combined with the supported Fabry–Perot (F–P)
cavity in the nanowire leads to the strong amplified spontaneous emission
(ASE). Detailed studies of the amplified cavity mode are carried out
by spatial–spectral photoluminescence (PL) imaging, where emission
from nanowire is resolved both spatially and spectrally. Resonant
emission is generated at nanowire ends and is polarized perpendicular
to the nanowire, in agreement with the simulated polarization characteristics
of the TE01 mode in the nanowire. The observation of strong ASE for
single QW nanowire at room temperature shows the potential application
of GaAs<sub>1–<i>x</i></sub>Sb<sub><i>x</i></sub> QW nanowires as low threshold infrared nanowire lasers
Polarization Tunable, Multicolor Emission from Core–Shell Photonic III–V Semiconductor Nanowires
We demonstrate luminescence from both the core and the
shell of
III–V semiconductor photonic nanowires by coupling them to
plasmonic silver nanoparticles. This demonstration paves the way for
increasing the quantum efficiency of large surface area nanowire light
emitters. The relative emission intensity from the core and the shell
is tuned by varying the polarization of the excitation source since
their polarization response can be independently controlled. Independent
control on emission wavelength and polarization dependence of emission
from core–shell nanowire heterostructures opens up opportunities
that have not yet been imagined for nanoscale polarization sensitive,
wavelength-selective, or multicolor photonic devices based on single
nanowires or nanowire arrays
Selective-Area Epitaxy of Pure Wurtzite InP Nanowires: High Quantum Efficiency and Room-Temperature Lasing
We report the growth of stacking-fault-free
and taper-free wurtzite
InP nanowires with diameters ranging from 80 to 600 nm using selective-area
metal–organic vapor-phase epitaxy and experimentally determine
a quantum efficiency of ∼50%, which is on par with InP epilayers.
We also demonstrate room-temperature, photonic mode lasing from these
nanowires. Their excellent structural and optical quality opens up
new possibilities for both fundamental quantum optics and optoelectronic
devices