tailieunhanh - Báo cáo "The dependence of the nonlinear absorption coefficient of strong electromagnetic waves caused by electrons confined in rectangular quantum wires on the temperature of the system"

The nonlinear absorption of a strong electromagnetic wave caused by confined electrons in cylindrical quantum wires is theoretically studied by using the quantum kinetic equation for electrons. The problem is considered in the case electron-acoustic phonon scattering. Analytic expressions for the dependence of the nonlinear absorption coefficient of a strong electromagnetic wave by confined electrons in rectangular quantum wires on the temperature T are obtained. | VNU Journal of Science Mathematics - Physics 26 2010 115-120 The dependence of the nonlinear absorption coefficient of strong electromagnetic waves caused by electrons confined in rectangular quantum wires on the temperature of the system Hoang Dinh Trien Bui Thi Thu Giang Nguyen Quang Bau Faculty of Physics Hanoi University of Science Vietnam National University 334 Nguyen Trai Thanh Xuan Hanoi Vietnam Received 23 December 2009 Abstract. The nonlinear absorption of a strong electromagnetic wave caused by confined electrons in cylindrical quantum wires is theoretically studied by using the quantum kinetic equation for electrons. The problem is considered in the case electron-acoustic phonon scattering. Analytic expressions for the dependence of the nonlinear absorption coefficient of a strong electromagnetic wave by confined electrons in rectangular quantum wires on the temperature T are obtained. The analytic expressions are numerically calculated and discussed for GaAs GaAsAl rectangular quantum wires. Keywords rectangular quantum wire nonlinear absorption electron- phonon scattering. 1. Introduction It is well known that in one dimensional systems the motion of electrons is restricted in two dimensions so that they can flow freely in one dimension. The confinement of electron in these systems has changed the electron mobility remarkably. This has resulted in a number of new phenomena which concern a reduction of sample dimensions. These effects differ from those in bulk semiconductors for example electron-phonon interaction and scattering rates 1 2 and the linear and nonlinear dc electrical conductivity 3 4 . The problem of optical properties in bulk semiconductors as well as low dimensional systems has also been investigated 5-10 . However in those articles the linear absorption of a weak electromagnetic wave has been considered in normal bulk semiconductors 5 in two dimensional systems 6-7 and in quantum wire 8 the nonlinear absorption of a strong .