A novel proposal for ultra-high optical nonlinearity in GaN/AlGaN spherical centered defect quantum dot (SCDQD)

Ultra-high detectivity room temperature THZ-IR photodetector based on resonant tunneling spherical centered defect quantum dot (RT-SCDQD)

“…It is observed that increasing the defect size increases the energy levels are but the difference between the energy levels decreases. The illustrated decrease in energy levels difference with defect size is related to the fact that the ground state is affected more than the first excited state [9]. Finally, increasing the mole fraction decreases the difference between energy levels.…”

“…It is obvious that these problems degrade device performance [8]. So it will be interesting to obtain long wavelength transition resonances without increasing the size of the quantum structure and increasing the absorption peak in lower energies [9]. We will show that it is possible to increase the absorption coefficient of the proposed structure with introducing a defect to center of quantum dot, without increasing the dot size.…”

“…1a. In this structure, we consider a spherical quantum dot with radius b then a spherical defect with radius a (Al x Ga 1Àx N-based) inserted in center of dot [9]. Finally a resonant tunneling double barrier is attached to the system.…”

“…The peak position wavelength varies in range k $ 8.6-13 lm with variation of monolayer numbers (between 10 and 60). While these QDs have been demonstrated successfully in mid-infrared wavelength photodetectors, the promise of new applications at longer wavelengths in the far-infrared (30-300 lm) or terahertz (1)(2)(3)(4)(5)(6)(7)(8)(9)(10) regions of the spectrum is providing motivation to extend their operating wavelength [6].…”

GaN/PMMA nanocomposite: synthesis and optical properties

“…When the nanosized semiconductor is distributed in an optically transparent matrix, quantum size effects are reported to be very important. Furthermore, it would expect an enhancement in the third-order nonlinear optical susceptibility Χ3 [12]. At same time, by varying the size of the nanocrystals, one can alter the emitted photon frequencies, thus potentially opening the way for applications of these composite materials as tunable optoelectronic devices [13][14].…”