We demonstrate mid-infrared electroluminescence from intersublevel transitions in self-assembled InAs quantum dots
coupled to surface plasmon modes on metal hole arrays. Subwavelength metal hole arrays with different periodicity are
patterned into the top contact of the broadband (9-15 μm) quantum dot material and the measured electroluminescence
is compared to devices without a metal hole array. The resulting normally directed emission is narrowed and a splitting
in the spectral structure is observed. By applying a coupled quantum electrodynamic model and using reasonable values
for quantum dot distributions and plasmon linewidths we are able to reproduce the experimentally measured spectral
characteristics of device emission when using strong coupling parameters.
We demonstrate room temperature electroluminescence from intersublevel transitions in self-assembled InAs quantum
dots in GaAs/AlGaAs heterostructures. The quantum dot devices are grown on GaAs substrates in a Varian Gen II
molecular beam epitaxy system. The device structure is designed specifically to inject carriers into excited conduction
band states in the dots and force an optical transition between the excited and ground states of the dots. A downstream
filter is designed to selectively extract carriers from the dot ground states. Electroluminescence measurements were
made by Fourier Transform Infrared Spectroscopy in amplitude modulation step scan mode. Current-Voltage
measurements of the devices are also reported. In addition, both single period and multi-period devices are grown,
fabricated, characterized, and compared to each other. Finally, we discuss the use of plasmonic output couplers for these
devices, and discuss the unique emission observed when the quantum dot layer sits in the near field of the plasmonic top
Straightforward extension of canonical microwave metamaterial structures to optical and IR frequency dimensions is
complicated by both the size scale of the resulting structures, requiring cutting edge lithography to achieve the requisite
line-widths, as well as limitations on assembly/construction into final geometry. We present a scalable fabrication
approach capable of generating metamaterial structures such as split ring resonators and split wire pairs on a micron/sub-micron
size scale on concave surfaces with a radius of curvature ~ SRR diameter. This talk outlines the fabrication
method and modeling/theory based interpretation of the implications of curved metamaterial resonators.
Interband and intersubband transitions in self-assembled InAs quantum dots embedded in an InGaAs graded
well have been investigated for their use in visible to mid-infrared (0.4 - 20 μm) detection applications. The materials
were grown by molecular beam epitaxy and characterized using atomic force microscopy and photoluminescence.
Devices were fabricated from the multiple quantum dot structures in order to measure the normal incident photoresponse
at 77 and 300 K. In addition, the dark current was measured in the temperature range of 77 - 300 K for the devices. A
dual broadband photoresponse from the interband and intersubband transitions was measured to be 0.5 to 1.0 μm and 2.0
to 14.0 μm, respectively.