TERAHERTZ EMISSION FROM ELECTRICALLY PUMPED SILICON GERMANIUM INTERSUBBAND DEVICES

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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Second‐harmonic generation using heavy‐hole/light‐hole intersubband transitions in asymmetric quantum wells

Applied Physics Letters ◽

10.1063/1.109499 ◽

1993 ◽

Vol 62 (16) ◽

pp. 1946-1948 ◽

Cited By ~ 18

Author(s):

Xiaohua H. Qu ◽

Harry Ruda

Keyword(s):

Second Harmonic Generation ◽

Quantum Wells ◽

Harmonic Generation ◽

Heavy Hole ◽

Second Harmonic ◽

Light Hole ◽

Intersubband Transitions ◽

Asymmetric Quantum

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Calculation of Modal Gain for Terahertz Lasers Based on HgCdTe Heterostructures with Quantum Wells

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156416400188 ◽

2016 ◽

Vol 25 (03n04) ◽

pp. 1640018 ◽

Cited By ~ 2

Author(s):

Alexander A. Dubinov ◽

Vladimir Ya. Aleshkin

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Heavy Hole ◽

Light Hole ◽

Modal Gain ◽

Terahertz Lasers

In this work we calculate and analyze modal gain for terahertz lasers based on HgCdTe heterostructures with quantum wells (QWs) taking into account the symmetry-enforced light hole-heavy hole mixing at the quantum well interfaces. We have found that modal gain for a structure with 5 HgTe QWs of the 5.2 nm width can be 33 cm−1 at 9 THz.

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TERAHERTZ EMITTERS AND DETECTORS BASED ON SiGe NANOSTRUCTURES

International Journal of Nanoscience ◽

10.1142/s0219581x0400195x ◽

2004 ◽

Vol 03 (01n02) ◽

pp. 171-176

Author(s):

J. KOLODZEY ◽

T. N. ADAM ◽

R. T. TROEGER ◽

P.-C. LV ◽

S. K. RAY ◽

...

Keyword(s):

Quantum Wells ◽

Silicon Germanium ◽

Molecular Beam ◽

Heavy Hole ◽

State Transitions ◽

Intersubband Transitions ◽

Boron Doped ◽

Different Types ◽

Device Applications ◽

Dopant Atoms

Terahertz (THz) electroluminescence was produced by three different types of sources: intersubband transitions in silicon germanium quantum wells, resonant state transitions in boron-doped strained silicon germanium layers, and hydrogenic transitions from dopant atoms in silicon. The devices were grown by molecular beam epitaxy, fabricated by dry etching, and characterized by infrared spectroscopy. The absorption of THz was observed in silicon germanium quantum wells at energies corresponding to heavy hole and light hole intersubband transitions. These results suggest that SiGe nanotechnology is attractive for THz device applications.

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Terahertz emission in single quantum wells after coherent optical excitation of light hole and heavy hole excitons

Physical Review Letters ◽

10.1103/physrevlett.69.3800 ◽

1992 ◽

Vol 69 (26) ◽

pp. 3800-3803 ◽

Cited By ~ 150

Author(s):

Paul C. M. Planken ◽

Martin C. Nuss ◽

Igal Brener ◽

Keith W. Goossen ◽

Marie S. C. Luo ◽

...

Keyword(s):

Quantum Wells ◽

Heavy Hole ◽

Optical Excitation ◽

Light Hole ◽

Single Quantum ◽

Terahertz Emission

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Valence Band Mixing in GaAs/AlGaAs Quantum Wells Adjacent to Self-Assembled InAlAs Antidots

Journal of Nanomaterials ◽

10.1155/2019/5349291 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

Takuya Kawazu

Keyword(s):

Optical Properties ◽

Quantum Wells ◽

Valence Band ◽

Energy Barrier ◽

Heavy Hole ◽

Electronic States ◽

Light Hole ◽

Photoluminescence Excitation ◽

Band Mixing ◽

Valence Band Mixing

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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Внутризонное поглощение излучения дырками в квантовых ямах InAsSb/AlSb и InGaAsP/InP

Физика и техника полупроводников ◽

10.21883/ftp.2018.02.45445.8645 ◽

2018 ◽

Vol 52 (2) ◽

pp. 207

Author(s):

Н.В. Павлов ◽

Г.Г. Зегря ◽

А.Г. Зегря ◽

В.Е. Бугров

Keyword(s):

Quantum Well ◽

Quantum Wells ◽

Incident Radiation ◽

Radiation Absorption ◽

Hole Density ◽

Internal Radiation ◽

Radiation Losses ◽

Semiconductor Quantum Wells ◽

Quantum Well Width ◽

Split Band

AbstractMicroscopic analysis of intraband radiation absorption by holes with their transition to the spin-split band for InAsSb/AlSb and InGaAsP/InP semiconductor quantum wells is performed in the context of the four-band Kane model. The calculation is performed for two incident-radiation polarizations: along the crystal-growth axis and in the quantum-well plane. It is demonstrated that absorption with transition to the discrete spectrum of spin-split holes has a higher intensity than absorption with transitions to the continuous spectrum. The dependences of the intraband absorption coefficient on temperature, hole density, and quantum- well width are thoroughly analyzed. It is shown that intraband radiation absorption can be the main mechanism of internal radiation losses in lasers based on quantum wells.

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