• 7,408,996 - Intersubband quantum box stack lasers, granted Aug 2008.
• 7,403,552 - High efficiency intersubband semiconductor lasers, granted Jul 2008.
• 6,907,056 - Semiconductor light sources with doping gradients in optical confinement layers for improved device efficiency, granted Aug 2003.
• 6,885,686 - High coherent power, two-dimensional surface-emitting semiconductor diode array laser, granted Jan 2003.
• 6,363,092 - Narrow spectral width high power distributed feedback semiconductor lasers, granted Jan 2001.
• 6,810,053 - Single mode, single lobe surface emitting distributed feedback semiconductor laser, granted Aug 2000.
• 6,219,365 - High performance aluminum free active region semiconductor lasers, granted Nov 1998.
• 6,229,153 - High peak current density resonant tunneling diode, granted Jun 1997.

• "Characteristics of mid-IR-emitting deep-well quantum cascade lasers grown by MOCVD"

Shin JC, D'Souza M, Kirch J, Park JH, Mawst LJ, Botez D, Journal of Crystal Growth 312(8): 1379-1382 Apr 2010.  Fabricated ridge-guide devides, lasting at similar 4.8 mu m, exhibit ultra-low temperature sensitivity of their electro-optical characteristics by comparison to those of conventional QC lasers emitting in the 4.5-5.5 mu m wavelength range. 

• "Passivation of interfacial states for GaAs and InGaAs/InP-based regrown nanostructures"

Rathi MK, Tsvid G, Khandekar AA, et al., Journal of Electronic Materials 38 (10): 2023-2032 Oct 2009. The interfacial charge density of regrown structures was studied for severala different pound material systems: GaAs, InGaAs/InP, and InAlAs-InGaAs superlattice structures on InP. The particular application of interest is in thea fabrication pound of nanoscale devices. Such structures require a very low density of interfacial charge at their exposed surfaces in order to avoid Fermi-level pinning and subsequent lateral carrier depletion across the structure.

• "InGaAs/GaAsP/AlGaAs, deep-well, quantum-cascade light-emitting structures grown by metalorganic chemical vapor deposition"

Xu DP, D'Souza M, Shin JC, et al., Journal of Crystal Growth 310 (7-9): Sp. Iss. SI 2370-2376 Apr 2008. InGaAs/GaAsP/AlGaAs strain-compensated, deep-well quantum-cascade (QC) structures have been grown by low-pressure metalorganic chemical vapor deposition (MOCVD). The structures were evaluated by high-resolution X-ray diffraction (HRXRD), transmission electron microscopy (TEM), and fabricated into narrow-ridge QC light emitters for electroluminescence characterization. The HRXRD patterns and cross-sectional TEM images show that well-controlled InGaAs/GaAsP/AlGaAs QC structures can be achieved via MOCVD growth.

• "Phonon confinement and electron transport in GaAs-based quantum cascade structures"

Gao X, Botez D, Knezevic I, Journal of Applied Physics 103 (7): 073101 Apr 2008. We present a detailed investigation of the effects that optical-phonon confinement has on the electronic transport properties of GaAs-based midinfrared multiple-quantum-well (MQW) quantum cascade lasers (QCLs).

• "Design and simulation of deep-well GaAs-based quantum cascade lasers for 6.7 mu m room-temperature operation"

Gao X, D'Souza M, Botez D, et al., Journal of Applied Physics 102 (11): Art. No. 113107 Dec 2007. We present the design and simulation of a GaAs-based quantum cascade laser (QCL) emitting at 6.7 mu m, the shortest room-temperature lasing wavelength projected to date for GaAs-based QCLs. This is achieved by introducing compressive strain only in the active quantum wells, where the optical transition occurs.

• "Progress towards intersubband quantum-box lasers for highly efficient continuous wave operation in the mid-infrared"

Botez D, Tsvid G, D'Souza M, Rathi M, Shin JC, et al., Journal of Nanophotonics 3: 031606 2009. 

• Intra-University Collaboration: Reed Center for Photonics, Profs. Luke J. Mawst, Thomas Kuech and I. Knezevic

• Reed Center for Photonics
• Wisconsin Center for Applied Microelectronics