volume | PIER Journals

Abstract

The analytic expressions for the absorption coefficient (ACF) of a weak electromagnetic wave (EMW) by confined electrons in rectangular quantum wires (RQWs) in the presence of laser radiation modulated by amplitude are calculated by using the quantum kinetic equation for electrons with the electron-optical phonon scattering mechanism. Then, the analytic results are numerically calculated and discussed for GaAs/GaAsAl RQWs. The numerical results show that the ACF of a weak EMW in a RQW can have negative values, which means that in the presence of laser radiation (non-modulated or modulated by amplitude), under proper conditions, the weak EMW is increased. This is different from the similar problem in bulk semiconductors and from the case of the absence of laser radiation. The results also show that in some conditions, when laser radiation is modulated by amplitude, ability to increase a weak EMW can be enhanced in comparison with the use of non-modulated laser radiation.

1. Tsu, R. and L. Esaki, "Tunneling in a finite superlattice," Appl. Phys. Lett., Vol. 22, No. 11, 562, 1973.
doi:10.1063/1.1654509

2. Harris Jr., J. S., "From bloch functions to quantum wells," J. Mod. Phys. B, Vol. 4, 1149, 1990.
doi:10.1142/S0217979290000577

3. Bau, N. Q. and T. C. Phong, "Calculations of the absorption coefficient of a weak electromagnetic wave by free carriers in quantum wells by the Kubo-Mori method," J. Phys. Soc. Jpn., Vol. 67, 3875, 1998.
doi:10.1143/JPSJ.67.3875

4. Bau, N. Q., L. Dinh, and T. C. Phong, "Absorption coefficient of weak electromagnetic waves caused by confined electrons in quantum wires," J. Korean. Phys. Soc., Vol. 51, No. 4, 1325, 2007.
doi:10.3938/jkps.51.1325

5. Bau, N. Q. and H. D. Trien, "The nonlinear absorption of a strong electromagnetic wave in lowdimensional systems," Wave Propagation, Ch. 22, 461, Intech, Croatia, 2011.

6. Bau, N. Q. and H. D. Trien, "The nonlinear absorption coefficient of strong electromagnetic waves caused by electrons confined in quantum wires," J. Korean. Phys. Soc., Vol. 56, No. 1, 120, 2010.
doi:10.3938/jkps.56.120

7. Pavlovich, V. V. and E. M. Epshtein, "Quantum theory of absorption of electromagnetic wave by free carries in semiconductors," Sov. Phys. Solid State, Vol. 19, 1760, 1977.

8. Malevich, V. L. and E. M. Epshtein, "Nonlinear optical properties of conduction electrons in semiconductors," Sov. Quantum Electronic, Vol. 1, 1468, 1974.

9. Nhan, N. V., N. T. T. Nhan, N. Van. Nghia, S. T. L. Anh, and N. Q. Bau, "Ability to increase a weak electromagnetic wave by confined electrons in quantum wells in the presence of laser radiation," PIERS Proceeding, 1054-1059, Kuala Lumpur, Malaysia, Mar. 27-30, 2012.

10. Nhan, N. T. T. and N. V. Nhan, "Calculation absorption coefficient of a weak electromagnetic wave by confined electrons in cylindrical quantum wires in the presence of laser radiation by using the quantum kinetic equation," Progress In Electromagnetics Research M, Vol. 34, 47-54, 2014.
doi:10.2528/PIERM13081207

11. Bau, N. Q. and C. Navy, "Influence of laser radiation (non-modulated and modulated) on the absorption of a weak electromagnetic wave by free electrons in semiconductor superlattices," VNU. Journal of Science, Nat. Sci., Vol. 13, No. 2, 26, 1997.

12. Mickevicius, R. and V. Mitin, "Acoustic-phonon scattering in a rectangular quantum wire," Phys. Rev. B, Vol. 48, 17194-17201, 1993.
doi:10.1103/PhysRevB.48.17194

13. Ariza-Flores, A. D. and I. Rodriguez-Vargas, "Electron subband structure and mobility trends in P-N delta-doped quantum wells in Si," Progress In Electromagnetics Research Letters, Vol. 1, 159-165, 2008.
doi:10.2528/PIERL07120607

Dr. Nguyen Thi Thanh Nhan

Dr. Dinh Quoc Vuong