Strain-induced heavy-hole-to-light-hole energy splitting in (111)BpseudomorphicInyGa1−yAs quantum wells

Optical properties of GaAs/AlGaAs quantum wells (QWs) in the vicinity of InAlAs quantum dots (QDs) were studied and compared with a theoretical model to clarify how the QD strain affects the electronic states in the nearby QW. In0.4Al0.6As QDs are embedded at the top of the QWs; the QD layer acts as a source of strain as well as an energy barrier. Photoluminescence excitation (PLE) measurements showed that the QD formation leads to the increase in the ratio Ie-lh/Ie-hh of the PLE intensities for the light hole (lh) and the heavy hole (hh), indicating the presence of the valence band mixing. We also theoretically calculated the hh-lh mixing in the QW due to the nearby QD strain and evaluated the PLE ratio Ie-lh/Ie-hh.

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Effects of intervalence band coherences on the coherently coupled heavy-hole–light-hole Stark shift in semiconductor quantum wells

Physical Review B ◽

10.1103/physrevb.65.245325 ◽

2002 ◽

Vol 65 (24) ◽

Cited By ~ 12

Author(s):

I. Rumyantsev ◽

N. H. Kwong ◽

R. Takayama ◽

R. Binder

Keyword(s):

Quantum Wells ◽

Heavy Hole ◽

Stark Shift ◽

Light Hole ◽

Semiconductor Quantum Wells

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Momentum-space solution of exciton excited states and heavy-hole–light-hole mixing in quantum wells

Physical Review B ◽

10.1103/physrevb.48.8210 ◽

1993 ◽

Vol 48 (11) ◽

pp. 8210-8221 ◽

Cited By ~ 51

Author(s):

Calvin Yi-Ping Chao ◽

Shun Lien Chuang

Keyword(s):

Quantum Wells ◽

Excited States ◽

Momentum Space ◽

Heavy Hole ◽

Light Hole ◽

Space Solution

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TERAHERTZ EMISSION FROM ELECTRICALLY PUMPED SILICON GERMANIUM INTERSUBBAND DEVICES

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156407004321 ◽

2007 ◽

Vol 17 (01) ◽

pp. 115-120

Author(s):

N. Sustersic ◽

S. Kim ◽

P.-C. Lv ◽

M. Coppinger ◽

T. Troeger ◽

...

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Silicon Germanium ◽

Heavy Hole ◽

Light Hole ◽

Spectral Lines ◽

Intersubband Transitions ◽

Terahertz Emission ◽

Drive Current ◽

Quantum Well Width

In this paper, we report on current pumped THz emitting devices based on intersubband transitions in SiGe quantum wells. The spectral lines occurred in a range from 5 to 12 THz depending on the quantum well width, Ge concentration in the well, and device temperature. A time-averaged power of 15 nW was extracted from a 16 period SiGe/Si superlattice with quantum wells 22 Å thick, at a device temperature of 30 K and a drive current of 550 mA. A net quantum efficiency of approximately 3 × 10-4 was calculated from the power and drive current, 30 times higher than reported for comparable quantum cascades utilizing heavy-hole to heavy-hole transitions and, taking into account the number of quantum well periods, approximately four times larger than for electroluminescence reported previously from a device utilizing light-hole to heavy-hole transitions.

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PHOTOCONDUCTIVITY, PHOTOREFLECTANCE AND PHOTOLUMINESCENCE OF GaAs-AlAs MULTIPLE QUANTUM WELLS

MRS Proceedings ◽

10.1557/proc-56-289 ◽

1985 ◽

Vol 56 ◽

Cited By ~ 1

Author(s):

H. NEFF ◽

K. J. BACHMANN ◽

W. D. LAIDIG

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Heavy Hole ◽

Multiple Quantum Well ◽

Light Hole ◽

Multiple Quantum ◽

Indirect Transition ◽

Temperature Dependent ◽

Direct Inter ◽

Phonon Absorption

AbstractEmploying temperature dependent photoconductivity, photoluminescence and photoreflectivity measurements, we have analyzed a GaAs-AlAs multiple quantum well. The above optical techniques clearly resolve the fundamental inter-subband transitions, including heavy hole-light hole splittings. At T < 60K an anomalously high photoconductivity was discovered below the direct inter-subband transitions and is attributed tentatively to the presence of extrinsic interface states within the bandgap. For T > l00K the fundamental indirect transition was discovered and associated with LO (L) - phonon absorption.

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