Optical bistability in Cd(x)Hg(1-x)Te

Claus F. Klingshirn, M. Wegener, Claus Dörnfeld +3 more

Jizhou Liu, Xuezhong Wang, Chenjia Chen +1 more

Magneto-optical bistability in diluted magnetic semiconductor Cd 1-x Mn x Te is realized. The bistability is created by the giant Faraday effect in Cd 1-x Mn x Te and the saturation characteristic of the magneto-optical feedback system. The bistability characteristic depends on the orientation angle α of the polarizers of the Faraday modulator and on the temperature of the sample.

D. Craig, M.R. Dyball, Alan Miller

Qiuhu Shi, Ya-wen Yang

We have observed bistability of the n-type Cd x Hg1− x Te in Auger-dominated in the following conditions: the input probe beam, obtained by splitting the CO2 laser with a ZnSe splitter, was incident upon the CdHgTe detector 1. The output probe beam, passing through the Fabry-Perot etalon, was detected by the CdHgTe detector 2. All beams were chopped using a mechanical chopper with a tunable mark/space ratio between 20:1 at a high speed synchronous motor. The signals of the incident and transmission intensity synchronously detected by using the CdHgTe detectors at 77 K were displayed on an oscilloscope. Our specimen was n-type Cd x Hg1− x Te (x = 0.225) at 77 K, the intrinsic carrier concentration n = 9.8 × 1014 cm-3, the mobility μ = 3.15 × 104 (cm2/V sec). The absorption coefficient α = 72 cm was polished plane parallel to form an etalon 215 μm thick, the reflectivities of which are R F = R B = R = 32%. In our experiment, the incident intensity I is 750 W/cm2 and both the laser mode and power stability met the standards.

Alan Miller, J. Staromlynska, Ian T. Muirhead +3 more

M. Czajkowski, L. Krause

The transfer of excitation energy induced in inelastic collisions between excited Hg atoms and ground-state Cd atoms was studied using methods of sensitized fluorescence. Hg atoms in a low-density Hg–Cd vapor mixture were excited with Hg 2537 Å resonance radiation to the 63P1 state and interacted with the Cd atoms which became collisionally excited to the 53P1 state and subsequently decayed emitting sensitized fluorescence. Measurements of relative intensities of Hg 2537 Å resonance fluorescence and Cd 3261 Å sensitized fluorescence yielded the cross section Q(63P1 → 53P1) = 4.6 × 10−2 Å2. The efficiency of the excitation transfer was enhanced by the addition of small quantities of N2 to the Hg–Cd system. The cross section for quenching of the Cd 53P1 state by collisions with N2 was found to be 1.7 Å2.