Transfer Matrix method for computation of electron transmission through aperiodic MQW
This paper presents the Eigen values and corresponding Eigen functions for the electron states in an aperiodic and asymmetric Multiple Quantum Well structure. A faster, simpler, and accurate algorithm based on Transfer Matrix method has been introduced for solving time independent Schrödinger equation in the most general case of aperiodic and asymmetric MQW structure. The MQWs are aperiodic with varying well and barrier widths and asymmetric i.e., having different materials and effective masses for the different regions of the wells and barriers. Adjacent wells are coupled through the barriers. Effect of barrier width on the tunneling properties has also been investigated. The theoretical results are compared with experimental results of Giorgetta et all [1]. Results of the computation based on the general model agree well with experimental data.
Spontaneous emission, light–current characteristics, and polarization bistability range in vertical-cavity surface-emitting lasers
A simple but generic phenomenological analytical theory for steady-state polarization properties of a vertical-cavity surface-emitting laser is developed. It is shown that a realistic amount of spontaneous emission in the laser mode and the saturation of the light–current curve can both significantly decrease the polarization bistability range.
Glycogen phosphorylase in lobster hepatopancreas: action of proteases on the enzyme
Abstract 1. 1. In lobster hepatopancreas, extracellular protreases cause the inactivation of glycogen phosphorylase. 2. 2. The proteolysis of glycogen phosphorylase purified from rabbit muscle by these proteases has been shown by SDS-polyacrylamide gel electrophoresis. 3. 3. A cell isolation technique has allowed us to remove proteases of extracellular digestion and to measure glycogen phosphorylase activity in lobster hepatopancreas. 4. 4. The glycogen phosphorylase activity seems to be mainly associated with R cells while it could not be detected in B cells.