- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Introduction to Quantum Electronics and Nonlinear Optics || Field Interaction with a??Free Chargesa??
摘要： The chapter discusses the interaction of electromagnetic fields with 'free charges' in plasma, focusing on the kinetic equation, cyclotron resonance, and fundamental absorption in semiconductors. It explores the classical and quantum mechanical descriptions of plasma behavior under external fields, including the effects of magnetic fields on electron motion and the absorption of electromagnetic waves by semiconductors.
关键词： semiconductors,plasma,cyclotron resonance,electromagnetic fields,free charges,kinetic equation,fundamental absorption
更新于2025-09-23 15:19:57
-
Laser processing of transparent semiconductor materials
摘要： A proposed method for laser processing of transparent semiconductor materials is based on thermal effect of increasing an absorption of light with a wavelength in the range of fundamental absorption-edge spectrum of the material. In this paper, we provide an analytical and experimental investigation of increase of absorption in semiconductor materials caused by laser radiation with wavelength in the range of absorption-edge of the material.
关键词： threshold intensity,fundamental absorption edge,laser,semiconductor,pulse
更新于2025-09-12 10:27:22
-
Band-fluctuations model for the fundamental absorption of crystalline and amorphous semiconductors: a dimensionless joint density of states analysis
摘要： We develop a band-fluctuations model which describes the absorption coefficient in the fundamental absorption region for direct and indirect electronic transitions in disordered semiconductor materials. The model accurately describes both the Urbach tail and absorption edge regions observed in such materials near the mobility edge in a single equation with only three fitting parameters. An asymptotic analysis leads to the universally observed exponential tail below the bandgap energy and to the absorption edge model at zero Kelvin above it, for either direct or indirect electronic transitions. The latter feature allows the discrimination between the absorption edge and absorption tails, thus yielding more accurate bandgap values when fitting optical absorption data. We examine the general character of the model using a dimensionless Joint Density of States formalism with a quantitative analysis of a large amount of optical absorption data. Both heavily doped p-type GaAs and nano-crystalline Ga1?xMnxN, as examples for direct bandgap materials, as well as amorphous Si:Hx, SiC:Hx and SiNx, are modeled successfully with this approach. We contrast our model with previously reported empirical models, showing in our case a suitable absorption coefficient shape capable of describing various distinct materials while also maintaining the universality of the exponential absorption tail and absorption edge.
关键词： band-fluctuations model,fundamental absorption,disordered semiconductor materials,absorption edge,Joint Density of States,Urbach tail
更新于2025-09-04 15:30:14