Giant enhanced four-wave mixing efficiency via two-photon resonance in asymmetric quantum wells

We present a study of optical phase conjugation through degenerate four-wave mixing in CuCl, as a function of light frequency, intensity, polarization and sample temperature. The phase-conjugate signal exhibits two maxima at the frequencies of the T 5 exciton (one-photon resonance) and of the biexciton (two-photon resonance). By appropriate combinations of the input beam polarizations, it is possible to single out the various terms contributing to the signal (small-spaced, large-spaced population grating and two-photon coherent excitation). The absolute value of X (3) responsible for the two-photon resonance has been determined ( x (3) (-w,w,w, -w) = 3.10 -7 e.s.u.). It leads to ‘mirror’ efficiencies of the order of 10% for input pump intensities I 0 » 10 5 W cm -2 and sample thickness d» 10 -4 cm. At higher I 0 , a saturation of the reflection takes place. The variation of the conjugate beam with temperature has been studied in the range 15 K < T <70 K. Finally, the phase-conjugate nature of the signal has been verified by inserting an aberrator in the path of the input probe beam, and by checking the reconstruction of the reflected beam.

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TRIPLET BIEXCITON TRANSITION UNDER HIGH MAGNETIC FIELD IN (Cd,Mn)Te/CdTe/(Cd,Mg)Te ASYMMETRIC QUANTUM WELLS

International Journal of Modern Physics B ◽

10.1142/s0217979204027402 ◽

2004 ◽

Vol 18 (27n29) ◽

pp. 3753-3756

Author(s):

HIROFUMI MINO ◽

AYUMU KOBAYASHI ◽

SHOJIRO TAKEYAMA ◽

GRZEGOSZ KARCZEWSKI ◽

TOMASZ WOJTOWICZ ◽

...

Keyword(s):

Magnetic Field ◽

Quantum Wells ◽

Four Wave Mixing ◽

Wave Mixing ◽

Spin States ◽

Exciton Resonance ◽

Single Quantum Well ◽

Asymmetric Quantum ◽

Time Region ◽

Spectrally Resolved

Biexciton spin states in a CdMnTe / CdTe / CdMgTe single quantum well have been investigated by means of the time-integrated and the spectrally-resolved four-wave mixing measurements in magnetic fields. Applying magnetic field in a Faraday geometry, the four-wave mixing signal showed a beat like structure at an early delay-time region with a co-circular (σ+,σ+) configuration. The spectrally-resolved four-wave mixing signals indicated an additional transition appeared at 1 meV higher energy side of the exciton resonance. These results were explained well by a magnetic field induced triplet biexciton transition.

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Theoretical Foundations for a New Family of Infrared Four-Wave Mixing Spectroscopies

Applied Spectroscopy ◽

10.1366/0003702971941601 ◽

1997 ◽

Vol 51 (7) ◽

pp. 949-958 ◽

Cited By ~ 31

Author(s):

John C. Wright ◽

Peter C. Chen ◽

James P. Hamilton ◽

Arne Zilian ◽

Mitchell J. Labuda

Keyword(s):

Mode Selection ◽

Four Wave Mixing ◽

Wave Mixing ◽

Raman Resonance ◽

Two Photon ◽

New Family ◽

Line Narrowing ◽

Raman And Infrared Spectroscopy ◽

Theoretical Foundations ◽

Photon Resonance

A new family of selective four-wave mixing methods, based on the establishment of vibrational nonlinear polarizations with multiple resonances, is proposed. This family includes double-infrared resonances, vibrationally enhanced Raman resonance, and vibrationally enhanced two-photon resonance. These methods are related to traditional Raman and infrared spectroscopy, but the methods are shown to have the capabilities for component and conformer selectivity, line-narrowing of inhomogeneously broadened vibrational transitions, and mode selection. The theoretical foundations for the methods are developed and directed to possible applications.

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