Narrow-Gap Semiconductors and Low-Dimensional Structures for Optoelectronic Applications

Advances in the growth, analysis, and characterization of various narrow-gap semiconductors and low-dimensional opto-electronic device structures have brought revolution into the modern day's information and communication technology including optical communication and computing systems. The main objective of this special issue is to include the recent advances in the experimental and theoretical research related to the growth, transport, and infrared properties of narrow-gap semiconductors and the fabrication, characterization, analysis, and simulation of various low-dimensional devices including quantum and nanostructures using narrow-gap semiconductors for optoelectronic applications. The basic aim of this special issue is to bring together in one publication the outstanding papers reporting new and original theoretical, experimental, and/or simulation works in the areas related to the narrow-gap semiconductors and low-dimensional structures. Among a large number of submissions received from various researchers, we have selected only 7 papers for publication in this special issue. The work reported by H. Cui et al. is believed to be very useful in understanding the effects of metal-semiconductor contacts on the transient photovoltaic characteristics of HgCdTe-based photovoltaic arrays by using ultrafast lasers. In another paper, H. Cui et al. have analyzed the electrical modulation properties of the output intensity of two-photon absorption (TPA) pumping in HgCdTe pho-todiodes, which could be interesting for controlling a steady output intensity of TPA by adjusting electric field in HgCdTe-based photodetectors. Both papers of H. Cui et al. are highly important for the design, fabrication, and characterization of HgCdTe-based infrared photodetectors. The paper of D. P. Samajdar and S. Dhar reports a mathematical model for investigating the valence band structure of alloy systems InAs 1−x Bi x and InSb 1−x Bi x by using the concept of valence-band anticrossing technique. The theoretical results for band structure of InAs 1−x Bi x and InSb 1−x Bi x could be of immense importance for the designing of diluted Bi-doped narrow-gap InAs-and InSb-based mid-/long-wavelength optoelectronic devices. A two-dimensional simulation for the effects of donor-like surface traps on two-dimensional electron gas (2DEG) and drain current collapse of AlGaN/GaN high electron mobility transistors (HEMTs) has been investigated in detail by C. Yu et al. The paper of C. Zheng et al. reports the effects of same temperature GaN cap layer thickness on the quality of the InGaN quantum well material and the well/barrier interface of InGaN/GaN multiquantum-well based green light-emitting diodes grown on silicon substrates by MOCVD method. An interesting work on the phosphorescence of …