Photoluminescence and far-infrared absorption in Si-doped self-organized InAs quantum dots

Phillips, Jamie; Kamath, K.; Zhou, Xiuli; Chervela, N.; Bhattacharya, P.

doi:10.1063/1.119347

Cited by 78 publications

(33 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Subbandgap absorption has been demonstrated in InAs/GaAs QDs by transmission measurements revealing transitions from the IB to the CB [63], [64] at LT and from the VB to the IB [65], and by photoresponse measurements, revealing both transitions at LT [56]. Evidence of the electronic transition from the IB to the CB was also reported for the InAs/AlGaAs system by transmission measurements [64] at LT. The GaAs/AlGaAs QD system has been studied in the framework of the IB theory.…”

Section: ) Electroluminescecementioning

confidence: 70%

“…Radiative electronic relaxation from the IB to the VB has been detected for the InAs/GaAs system [56], [63], [64], [67], [68] and for the InAs/AlGaAs system [64], [67], [69]. It must be noticed, however, that no luminescence that can be attributed to photons arising from the relaxation of electrons from the CB to the IB has been reported yet.…”

Section: ) Electroluminescecementioning

confidence: 94%

See 1 more Smart Citation

Review of Experimental Results Related to the Operation of Intermediate Band Solar Cells

Ramiro

Martı́

Antolín

et al. 2014

IEEE J. Photovoltaics

View full text Add to dashboard Cite

Abstract-The intermediate band solar cell (IBSC) has drawn the attention of the scientific community as a means to achieve high-efficiency solar cells. Complete IBSC devices have been manufactured using quantum dots, highly mismatched alloys, or bulk materials with deep-level impurities. Characterization of these devices has led, among other experimental results, to the demonstration of the two operating principles of an IBSC: the production of the photocurrent from the absorption of two below bandgap energy photons and the preservation of the output voltage of the solar cell. This study offers a thorough compilation of the most relevant reported results for the variety of technologies investigated and provides the reader with an updated record of IBSC experimental achievements. A table condensing the reported experimental results is presented, which provides information at a glance about achievements, as well as pending results, for every studied technology.

show abstract

Section: ) Electroluminescecementioning

confidence: 70%

Section: ) Electroluminescecementioning

confidence: 94%

Review of Experimental Results Related to the Operation of Intermediate Band Solar Cells

Ramiro

Martı́

Antolín

et al. 2014

IEEE J. Photovoltaics

View full text Add to dashboard Cite

show abstract

“…These changes of PL spectra with the increase of excitation intensity finally saturate because the photogenerated electron-hole separation reduces, and finally cancels, the built-in electric field. Now we compare our PL results of the n-i-p-i sample with similar works, [3][4][5][6][7][8] where many-body effects ͑or charging effects͒ in QD's were investigated. In these studies, the QD's were filled with electrons by doping.…”

mentioning

confidence: 99%

Photoluminescence of InAs quantum dots inn-i-p-iGaAs superlattice

Wang

Chen

et al. 2000

Phys. Rev. B

View full text Add to dashboard Cite

Large blueshift and linewidth increase in photoluminescence ͑PL͒ spectra of InAs quantum dots ͑QD's͒ in n-i-p-i GaAs superlattice were observed. By increasing the excitation intensity from 0.5 to 32 W/cm 2 , the PL peak position blueshifted 18 meV, and the linewidth increased by 20 meV. Such large changes are due to the state-filling effects of the QD's resulted from the separation of photogenerated electrons and holes caused by the doping potential.The optical properties of InAs self-assembled quantum dots ͑QD's͒ have been of great interest in recent years. The interband and intraband optical transitions of these QD's are widely studied, both for the interest in fundamental physical properties and for the development of QD lasers and photodetectors. It is important to investigate electron-hole separation effects in QD's and design QD structures that can separate and store photoexcited carriers for memory-device applications. However, few works were done in this field. Recently, Schoenfeld et al.1 have designed a QD device that can separate and store photoexcited electrons and holes. Their structure consisted of two GaAs quantum wells of different thickness, separated by a thin AlAs barrier. An InAs QD layer is inserted in the thick quantum well. The strain these InAs QD's create induces QD's within the thin GaAs quantum well that are coupled to the InAs QD's in the thick well. In their structure, photogenerated electrons and holes are spatially separated into the InAs QD's and strain-induced QD's, respectively.In this work, we study a different QD structure designed to spatially separate and store photogenerated electrons and holes. In this structure, InAs self-assembled QD's were grown in the n-type and p-type regions of a n-i-p-i GaAs superlattice. Photogenerated electrons and holes in GaAs barriers are expected to be swept by the intrinsic electric field to the n-doped regions and the p-doped regions, respectively, and trapped by the InAs QD's there. As the photogenerated electrons and holes fill up the lower QD states, photoluminescence ͑PL͒ properties of these InAs QD's different from conventional QD's inserted in intrinsic GaAs layers are expected. In our PL experiments, large blueshift of the PL peak and increase of the PL linewidth with increasing excitation intensity were observed for the QD's in the n-i-p-i GaAs superlattice, whereas for similar InAs QD's in intrinsic GaAs layers, only a small blueshift of the PL peak and increase of the linewidth were observed. The large blueshift in the n-ip-i QD's is a clear indication of the state filling of the QD's due to electron-hole separation.The samples were grown by molecular-beam epitaxy on a ͑001͒ N ϩ GaAs substrate. After deposition of a 1-m semiinsulating GaAs type buffer layer, 10 periods of n-type GaAs ͑20 nm͒/InAs QD's (2 ML)/n-type GaAs (20 nm)/p-type GaAs ͑20 nm͒/InAs QD's (2 ML)/p-type GaAs ͑20 nm͒ were grown. The n-type regions were Si doped and the p-type regions were Be doped; both n and p doping concentrations are 1ϫ10 18 cm Ϫ3 . The growth t...

show abstract

“…In fact, an important advantage of the QDIP is that the device spectral response can be tuned throughout the IR spectrum (from ∼50 to 500 meV) by varying the QD heterostructure [66][67][68][69][70][71][72]. One variation of InAs/GaAs QDs involves including Ga in the InAs QD and/or Al in the GaAs barrier [6,46,73,74].…”

Section: Alternative Qd Materials Systemsmentioning

confidence: 99%

Quantum-dot infrared photodetectors: a review

Stiff‐Roberts

2009

J. Nanophoton

101

View full text Add to dashboard Cite

Abstract. Quantum-dot infrared photodetectors (QDIPs) are positioned to become an important technology in the field of infrared (IR) detection, particularly for high-temperature, low-cost, high-yield detector arrays required for military applications. High-operating temperature (≥150 K) photodetectors reduce the cost of IR imaging systems by enabling cryogenic dewars and Stirling cooling systems to be replaced by thermo-electric coolers. QDIPs are well-suited for detecting mid-IR light at elevated temperatures, an application that could prove to be the next commercial market for quantum dots. While quantum dot epitaxial growth and intraband absorption of IR radiation are well established, quantum dot nonuniformity remains as a significant challenge. Nonetheless, state-of-the-art mid-IR detection at 150 K has been demonstrated using 70-layer InAs/GaAs QDIPs, and QDIP focal plane arrays are approaching performance comparable to HgCdTe at 77 K. By addressing critical challenges inherent to epitaxial QD material systems (e.g., controlling dopant incorporation), exploring alternative QD systems (e.g., colloidal QDs), and using bandgap engineering to reduce dark current and enhance multi-spectral detection (e.g. resonant tunneling QDIPs), the performance and applicability of QDIPs will continue to improve.Keywords: InAs/GaAs quantum dots, colloidal quantum dots, quantum-dot infrared photodetectors, QDIP focal plane arrays.

show abstract

Photoluminescence and far-infrared absorption in Si-doped self-organized InAs quantum dots

Cited by 78 publications

References 14 publications

Review of Experimental Results Related to the Operation of Intermediate Band Solar Cells

Review of Experimental Results Related to the Operation of Intermediate Band Solar Cells

Photoluminescence of InAs quantum dots inn-i-p-iGaAs superlattice

Quantum-dot infrared photodetectors: a review

Contact Info

Product

Resources

About