Two-photon absorption of IR radiation and its optical saturation in n-type gallium antimonide

Abstract

Electron diffraction was used to study the stoichiometric dependence of the modulation wave vector in the incommensurately modulated structures of -and -Li x V 2 O 5 . For -Li x V 2 O 5 (0.32 x 0.52) and -Li x V 2 O 5 (0.52 x 0.80) the space group of the basic structure is P mmn, and the superspace group characterizing the one-dimensionally modulated structure is found to be P mmn (0 γ 1/2). The stoichiometry dependence of the modulation wave vector q can be described by a staircase function, with γ being constant at γ = 0.435(5) for -Li x V 2 O 5 . A second plateau has been observed in the stability field of -Li x V 2 O 5 for 0.550 x 0.575 with γ = 0.465(5). For the stoichiometry range 0.575 x 0.707, γ varies continuously between γ = 0.465(5) and γ = 0.565(5).In the present paper we will show that the system Li x V 2 O 5 can be described by an extended Frenkel-Kontorova model. Despite its extreme simplicity in the one-dimensional case, the model exhibits most of the features necessary for understanding the variation of the dependence of the modulation wave vector on the lithium stoichiometry.

Measurement and modeling of infrared nonlinear absorption coefficients and laser-induced damage thresholds in Ge and GaSb

“…It is noted that neither model provides an excellent fit to both data points; however the uncertainty range of each model may intersect the uncertainty range of the reported values. The 1996 study of Akmanov et al [16] at 2.94 m used an estimate of =2ϫ 10 −17 cm 2 which is 1 order of magnitude smaller than the values reported in this work (3.8ϫ 10 −16 cm 2 and 6.5ϫ 10 −16 cm 2 ). This results in a much higher fit to ␤, which is expected due to the inverse relationship between ␤ and that is visible in Fig.…”

“…4 (right). It was not possible to fit the transmission data from the 1996 study of Akmanov et al [16] using measured values from this work as the pulse width, level of linear transmission, spot size, and spatial profile were not reported.…”

“…GaSb is far less studied, and there is only one paper in which TPA was measured. In a 1996 work, Akmanov et al used an estimated =2ϫ 10 −17 cm 2 to measure ␤ = 380 cm/ GW in GaSb at a wavelength of 2.94 m [16]. At a wavelength of 2.05 m, a ␤ of 156 cm/GW was reported as a theoretical calculation for GaSb [17].…”

The Interband Cascade Laser

“…Were the free-carrier absorption cross-sections for the claddings and SCLs well known, we could estimate the net loss using the nominal doping densities. However, the literature values for n-GaSb display some spread [78,79], with typical mid-IR values on the order of 10 −17 cm −2 . Little information is available concerning free carrier absorption in the cladding materials, although the contributions of multiple, potentially-rough interfaces in the InAs/AlSb SLs, and alloy scattering in bulk Al(Ga)AsSb, implies that the free carrier absorption cross-sections are surely larger than in n-GaSb.…”

Two-photon absorption in colloidal semiconductor nanocrystals: a review

“…Since the first experimental studies of 2PA [3][4][5], research groups have focused on investigating the nonlinear absorption of different classes of materials, including bulk semiconductors [6][7][8][9][10][11][12], nanostructured semiconductors [13][14][15][16], and organic dyes [17][18][19][20][21][22]. The driving force for these studies has been the possibility to enable new technologies based on nonlinear light-matter interactions.…”