Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Philosophical Transactions of the Royal Society of London Series A Mathematical and Physical Sciences

Fast and sensitive nonlinear processes: bistability in CdHgTe

Alan Miller, Gareth Parry

Published Dec 18, 1984• 8 citations
Publisher

Abstract

Abstract We discuss the origin and characteristics of the very large intensity-dependent changes in the refractive index of the semiconductor cadmium mercury telluride at 10.6 m. With continuous wave (c.w.) radiation and sample temperatures of 77 K nonlinear Fabry-Perot effects can be observed at powers as low as 1 mW. The Auger dominated recombination process and the thermal contributions to the refractive index make observations of optical bistability difficult with c.w. radiation. However, the use of a pulsed CO2 laser and two-photon absorption of the radiation does lead to the observation of bistability at room temperature. We compare these results with the reported work on InSb.

DOI
10.1098/rsta.1984.0107

Related papers

Nonlinear Refraction and Increasing Absorption in HgCdTe Optical Bistability at Room Temperature: an Experimental Study

Peter Coppo, S. Cecchi, P. Salieri +1 more

Many authors have experimentally examined the nonlinearities of HgCdTe at resonance with the CO2 laser wavelength [1]. At room temperature non1inearities of electronic origin, arising from band filling, are weak because of Auger recombination and are masked by thermal effects. In this communication we extend the analysis of ref. 1 on thermally induced optical bistability at low power: we show, for the first time in HgCdTe, the appearance of clockwise hysteresis cycles in transmission as input power Pi is increased, due to nonlinear absorption. We can account for both absorptive and refractive nonlinear contributions by simultaneous monitoring of transmission and reflection. The Hg0.815Cd0.185Te plates (280 um in thickness, with doping pa =1*1016 cm-3, prepared and polished by Elettronica SpA) were placed without heatsinking in a thermally controlled environment. In Fig. 1 the transmitted (Pt) and reflected (Pr) power is shown as a function of Pi: the three data sets differ in cavity mistuning. The thermooptic effect was measured directly, by a close focus optical pyrometer, and indirectly by taking data at different thermal bath temperature T. The values of Pi at the hysteresis associated to a given cavity interference order (indicated with the symbols of Fig. 1c) drift with T (Fig. 2): the maximum induced temperature increase is inferred to be 30-35°C, with steps of 2.5-3.5°C at the switching points, and a value of dn/dT = -2.8*10-3 K-1 is deduced. Fig. 3 presents numerical results (to be compared with Fig. 1b) obtained parametrically solving the nonlinear Fabry Perot equations using the absorption measured after AR coating one sample face. This nonlinear absorption will be discussed in terms of a free carrier origin.

Topical Meeting on Optical Bistability (OB)•Jan 1, 1988•0 citations

Optical bistability in semiconductor CdHgTe etalon

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.

Annual Meeting Optical Society of America•Jan 1, 1991•0 citations

Optical Bistability And Transphasor Action In Semiconductors

David A. B. Miller, C. T. Seaton, Stanley Desmond Smith

We report the realisation of optically bistable switching and memory elements, and the transphasor Can all-optical transistor) in simple one element nonlinear Fabry-Perot interferometers made from the semiconductor InSb. These devices, which operate at 5 K and 77 K with mW powers from a cw CO laser between 5 and 6 μm rely on a strongly intensity-dependent refractive index discovered near the bandgap region of InSb and explained by bandgap resonant saturation. Switching speeds are shown to be < 500 ns in these first devices and operation to much shorter timescales is predicted. Operation at room temperature and in other semiconductors at other wavelengths remains a possibility and such devices offer considerable potential for all-optical switching in integrated optics and laser pulse control.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 15, 1981•1 citation

Optical bistability and signal amplification in a semiconductor crystal: applications of new low-power nonlinear effects in InSb

David A. B. Miller, Stanley Desmond Smith, A.M. Johnston

We report the observation of optical stability for a plane parallel semiconductor crystal which forms a Fabry-Perot interferometer using only the natural reflectivity of its surfaces. Nonlinear transmission is observed for cw laser intensities above ∼ 100 W/cm2 for radiation at 1895 cm−1 near the energy gap of InSb at 5 K. The effect is interpreted in terms of a very large intensity-dependent refractive index giving a 5λ/2 optical thickness change for an intensity of ∼2 kW/cm2. Clear bistability is seen in fifth-order interference, the first such observation above first order in an intrinsic, one-element system, in addition to regions exhibiting signal amplification. The same crystal also shows strong modulation of the transmission of one laser beam induced by a second, with real signal gain, thus demonstrating an ’’optical transistor.’’

Applied Physics Letters•Nov 1, 1979•310 citations

Nonlinear Fabry-Perot Etalon and Optical Bistability in CdHgTe at 77 K

Wu Xiaoguang, Xierong Hu, Yang Yawen +2 more

We report the first observations of nonlinear feature and optical bistability in n -CdHgTe at 77 K and obtained computer simulated curves, then discuss contribution due to thermal effect.

Chinese Physics Letters•Oct 1, 1992•3 citations

Recent advances in optical testability

Nasser N. Peyghambarian

Optical bistability can be obtained in nonlinear materials either with Fabry-Perot mirrors or without external feedback. When a material is placed between partially reflecting mirrors, a nonlinear Fabry-Perot etalon is formed with the etalon providing an external feedback. Optical bistability and gating occur as a result of a shift in the Fabry-Perot peak when the light intensity is increased (or when a second laser beam is introduced into the cavity). Optical bistability with the external feedback mechanism has been observed in many semiconductors such as bulk GaAs, GaAs-AIGaAs multiple-quantum-well (MQW) structures, InSb, InAs, CdS, CdHgTe, GaSe, and CuCI.

Conference on Lasers and Electro-Optics•Jan 1, 1986•0 citations
Abstract We discuss the origin and characteristics of the very large intensity-dependent changes in the refractive index of the semiconductor cadmium mercury telluride at 10.6 m. With continuous wave (c.w.) radiation and sample temperatures of 77 K nonlinear Fabry-Perot effects can be observed at powers as low as 1 mW. The Auger dominated recombination process and the thermal contributions to the refractive index make observations of optical bistability difficult with c.w. radiation. However, the use of a pulsed CO2 laser and two-photon absorption of the radiation does lead to the observation of bistability at room temperature. We compare these results with the reported work on InSb.
Many authors have experimentally examined the nonlinearities of HgCdTe at resonance with the CO2 laser wavelength [1]. At room temperature non1inearities of electronic origin, arising from band filling, are weak because of Auger recombination and are masked by thermal effects. In this communication we extend the analysis of ref. 1 on thermally induced optical bistability at low power: we show, for the first time in HgCdTe, the appearance of clockwise hysteresis cycles in transmission as input power Pi is increased, due to nonlinear absorption. We can account for both absorptive and refractive nonlinear contributions by simultaneous monitoring of transmission and reflection. The Hg0.815Cd0.185Te plates (280 um in thickness, with doping pa =1*1016 cm-3, prepared and polished by Elettronica SpA) were placed without heatsinking in a thermally controlled environment. In Fig. 1 the transmitted (Pt) and reflected (Pr) power is shown as a function of Pi: the three data sets differ in cavity mistuning. The thermooptic effect was measured directly, by a close focus optical pyrometer, and indirectly by taking data at different thermal bath temperature T. The values of Pi at the hysteresis associated to a given cavity interference order (indicated with the symbols of Fig. 1c) drift with T (Fig. 2): the maximum induced temperature increase is inferred to be 30-35°C, with steps of 2.5-3.5°C at the switching points, and a value of dn/dT = -2.8*10-3 K-1 is deduced. Fig. 3 presents numerical results (to be compared with Fig. 1b) obtained parametrically solving the nonlinear Fabry Perot equations using the absorption measured after AR coating one sample face. This nonlinear absorption will be discussed in terms of a free carrier origin.
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.
We report the realisation of optically bistable switching and memory elements, and the transphasor Can all-optical transistor) in simple one element nonlinear Fabry-Perot interferometers made from the semiconductor InSb. These devices, which operate at 5 K and 77 K with mW powers from a cw CO laser between 5 and 6 μm rely on a strongly intensity-dependent refractive index discovered near the bandgap region of InSb and explained by bandgap resonant saturation. Switching speeds are shown to be < 500 ns in these first devices and operation to much shorter timescales is predicted. Operation at room temperature and in other semiconductors at other wavelengths remains a possibility and such devices offer considerable potential for all-optical switching in integrated optics and laser pulse control.
We report the observation of optical stability for a plane parallel semiconductor crystal which forms a Fabry-Perot interferometer using only the natural reflectivity of its surfaces. Nonlinear transmission is observed for cw laser intensities above ∼ 100 W/cm2 for radiation at 1895 cm−1 near the energy gap of InSb at 5 K. The effect is interpreted in terms of a very large intensity-dependent refractive index giving a 5λ/2 optical thickness change for an intensity of ∼2 kW/cm2. Clear bistability is seen in fifth-order interference, the first such observation above first order in an intrinsic, one-element system, in addition to regions exhibiting signal amplification. The same crystal also shows strong modulation of the transmission of one laser beam induced by a second, with real signal gain, thus demonstrating an ’’optical transistor.’’
Optical bistability can be obtained in nonlinear materials either with Fabry-Perot mirrors or without external feedback. When a material is placed between partially reflecting mirrors, a nonlinear Fabry-Perot etalon is formed with the etalon providing an external feedback. Optical bistability and gating occur as a result of a shift in the Fabry-Perot peak when the light intensity is increased (or when a second laser beam is introduced into the cavity). Optical bistability with the external feedback mechanism has been observed in many semiconductors such as bulk GaAs, GaAs-AIGaAs multiple-quantum-well (MQW) structures, InSb, InAs, CdS, CdHgTe, GaSe, and CuCI.