The relationship between gain and carrier density is analysed. In the quantum well (QW) lasers, initially, the gain increases rapidly with the carrier density and then starts to saturate. It can be seen that QW lasers...The relationship between gain and carrier density is analysed. In the quantum well (QW) lasers, initially, the gain increases rapidly with the carrier density and then starts to saturate. It can be seen that QW lasers have a higher differential gain because of the step-like state density, and that the gain saturates at higher carrier densities because of the constant state density of the lowest subband. It is shown that simple logarithmic gain-carrier density is more accurate than the traditional linearized form for a QW laser.展开更多
In this paper, we obtain considerable spin-orbit （SO） parameters in AlxGa1-xN/GaN quantum wells （QWs） with sheet carrier concentration N8 = 120 × 10^11/cm^2. With increasing AI content （x） of the barrier, t...In this paper, we obtain considerable spin-orbit （SO） parameters in AlxGa1-xN/GaN quantum wells （QWs） with sheet carrier concentration N8 = 120 × 10^11/cm^2. With increasing AI content （x） of the barrier, the SO parameters increase as a whole, and the two major contributions are found to be the decrease of the expansion region of the envelope functions and the increase of the polarized electric field in the well. Compared with the Rashba parameters for the first two subbands, the intersubband SO parameter is a bit smaller and varies more slowly with x. The results indicate the SO parameters, especially the Rashba parameters can be engineered by the AI composition of the barrier, which may be helpful to the spin manipulation of III-nitride low-dimensional heterostructures.展开更多
The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using...The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using the program, Integrated System Engineering-Technical Computer Aided Design （ISE-TCAD）. Various thicknesses （6, 7, 8, 10, 12 rim） of AlxInyGa1-x-yN barriers with （3 nm） Al0.08In0.08Ga0.84N wells as an active region were studied. The lowest threshold current （lth）, and the highest output power （Pop） were 116 mA and 196 mW respectively, at barriers thickness of 6 nm, Al mole fraction of 10% and In mole fraction of 1%, at an emission wavelength of 359.6 nm.展开更多
文摘The relationship between gain and carrier density is analysed. In the quantum well (QW) lasers, initially, the gain increases rapidly with the carrier density and then starts to saturate. It can be seen that QW lasers have a higher differential gain because of the step-like state density, and that the gain saturates at higher carrier densities because of the constant state density of the lowest subband. It is shown that simple logarithmic gain-carrier density is more accurate than the traditional linearized form for a QW laser.
文摘In this paper, we obtain considerable spin-orbit （SO） parameters in AlxGa1-xN/GaN quantum wells （QWs） with sheet carrier concentration N8 = 120 × 10^11/cm^2. With increasing AI content （x） of the barrier, the SO parameters increase as a whole, and the two major contributions are found to be the decrease of the expansion region of the envelope functions and the increase of the polarized electric field in the well. Compared with the Rashba parameters for the first two subbands, the intersubband SO parameter is a bit smaller and varies more slowly with x. The results indicate the SO parameters, especially the Rashba parameters can be engineered by the AI composition of the barrier, which may be helpful to the spin manipulation of III-nitride low-dimensional heterostructures.
基金conducted under Science Fund,Cycle 2007,of The Ministry of Science,Technology and Innovation,MalaysiaThe financial support from Universiti Sains Malaysia is gratefully acknowledged
文摘The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using the program, Integrated System Engineering-Technical Computer Aided Design （ISE-TCAD）. Various thicknesses （6, 7, 8, 10, 12 rim） of AlxInyGa1-x-yN barriers with （3 nm） Al0.08In0.08Ga0.84N wells as an active region were studied. The lowest threshold current （lth）, and the highest output power （Pop） were 116 mA and 196 mW respectively, at barriers thickness of 6 nm, Al mole fraction of 10% and In mole fraction of 1%, at an emission wavelength of 359.6 nm.
