Search

Proposes a theoretical model of a multiquantum well infrared photodetectors (QWIP) detector made of GaAs/AlGaAs superlattice. Description of the proposed model; Calculation of the current response; Method used in calculating the dark current; Sources of noise in a QWIP detector; Formula of detectivity for the performance of a QWIP detector.

Two-dimensional photonic crystals with photonic bandgaps (PBGs) in the terahertz (THz) frequency regime have been constructed by arraying metal-coated cylinders. PBGs were observed at 2.2 and 4.7 THz for the samples with lattice constant of 140 and 70 μm, respectively. Experimental results show that the PBGs were realized with only a small number of layers (<=10 periods) and they are robust against positional disorder (about 14%). Thus, metal-coated cylinders provide us with a promising approach to create robust PBGs in the THz frequency range. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the lifetime of resonant levels of the double-barrier structure within a simple effective mass picture. Information on resonant tunneling; Effective mass of the electron; Results of the study.

The capacitance-voltage (C-V) behavior of the metal/Bi[sub 2]Ti[sub 2]O[sub 7]/n-Si metal-oxide-semiconductor (MOS) structure has been studied. The analyses of C-V curves show that a high builtin voltage of 11 V on Si can be achieved by bias-temperature (BT) process. The hysteresis loops in C-V curves of the MOS structure were also observed clearly. From the dependence of C-V properties on different BT processes, it is deduced that the hysteresis loops are dominated by the mobile negative charges in the oxide. [ABSTRACT FROM AUTHOR]