Acceptor levels in gallium arsenide (luminescence measurements)

White, A. M.; Dean, P.D.G.; Ashen, D.J.; Mullin, J. B.; Webb, M. D.; Day, Brian J.; Greene, P.D.

doi:10.1088/0022-3719/6/11/008

Cited by 50 publications

(7 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The strong feature labeled "CB → A" is attributed to the conduction band→ acceptor transition from the GaAs͑p͒ buffer. The identification of the latter is made on the basis of its energy 11,12 and the fact that its position does not change in LEDs which incorporate quantum wells with different well widths.…”

Section: Resultsmentioning

confidence: 99%

Phonon-assisted recombination in Fe-based spin LEDs

et al. 2006

View full text Add to dashboard Cite

The electroluminescence ͑EL͒ spectra from Fe/ AlGaAs͑n͒ / GaAs/ AlGaAs͑p͒ spin LEDs contain an e 1 h 1 excitonic feature; in addition, they exhibit new features not present in the photoluminescence ͑PL͒ spectra, that are "satellites" or "replicas" of the exciton. These satellites are red shifted with respect to e 1 h 1 by energies that are approximately equal to those of zone edge phonons in GaAs. The intensity of the replicas depends strongly on bias voltage. In the presence of a magnetic field the satellites become circularly polarized as + but their polarization is always lower than that of e 1 h 1. The satellites are interpreted as due to recombination processes that involve zone edge electrons that tunnel into the GaAs quantum well. These processes occur simultaneously with the emission of zone-edge phonons. Our interpretation is supported by a numerical simulation of the properties of electrons tunneling through an Fe/ GaAs͑n͒ Schottky barrier.

show abstract

Section: Resultsmentioning

confidence: 99%

Phonon-assisted recombination in Fe-based spin LEDs

et al. 2006

View full text Add to dashboard Cite

show abstract

“…The values of E th have been found to be either 1.483 or 1.493 eV [5] (depending on the QD surrounding) in accordance with the ionisation energies of the main acceptors in MBE grown GaAs, Si and C, respectively [7]. Figure 1 shows the temperature evolution of the QD PL spectra, measured with an excitation power P ex = 150 nW, for two excitation energies below and above E th , respectively.…”

Section: Resultsmentioning

confidence: 73%

“…This can be explained taking into account the creation of excess holes as a result of the thermally enhanced acceptor ionisation processes. As a first approximation we have calculated the concentration of thermally generated excess holes, p, in dark using Fermi statistics and the carbon ionisation energy (26 meV [7]) in the charge neutrality equation with an assumed acceptor concentration of 1x10 14 cm -3 [8]. For T > ~25 K, p grows quickly and around 35 K about half of the acceptors are ionised.…”

Section: Resultsmentioning

confidence: 99%

Temperature study of the photoluminescence of a single InAs/GaAs quantum dot

Karlsson¹,

Moskalenko²,

Holtz³

et al. 2004

phys. stat. sol. (c)

View full text Add to dashboard Cite

The temperature evolution of the micro-photoluminescence (PL) spectra of a single InAs/GaAs quantum dot is studied from 5 to 65 K for different excitation energies. For excitation energies within the shallow acceptor absorption region below the GaAs bandgap a strong increase of the PL intensity (more than 10 times) is observed at 45 K with respect to 5 K. Besides, with increasing the temperature the PL spectrum redistributes in favour of a more neutral exciton configuration, contrary to the tendency observed when exciting outside this region. The results are explained in terms of separate optical generation of excess electrons and thermal generation of excess holes via the shallow acceptor levels in the GaAs barriers, resulting in an efficient carrier diffusion in the wetting layer and capture into the quantum dot.

show abstract

“…This assignment is supported by the fact that the energy difference (38 meV) between the peak position and the GaAs bandgap at 73 K (1.508 eV) is close to the ionization energy of the Si shallow acceptor (34 meV) in GaAs. 24 The SPV vector representing this process is in the IV quadrant. Its increase rotates the overall SPV vector from II through III toward the IV quadrant.…”

Section: B Mechanisms Of Carrier Separation In Spacementioning

confidence: 99%

Optical properties of multi-layer type II InP/GaAs quantum dots studied by surface photovoltage spectroscopy

Ivanov

Germanova

Gomes

et al. 2011

Journal of Applied Physics

View full text Add to dashboard Cite

We present a low-temperature (73 K) study of the optical properties of multi-layer type II InP/ GaAs self-assembled quantum dots by means of surface photovoltage (SPV) spectroscopy, taking advantage of its high sensitivity and contactless nature. The samples contain 10 periods of InP quantum dot planes separated by 5 nm GaAs spacers. The SPV amplitude spectra reveal two major broad peaks, situated at low and high energies, respectively. These features are analyzed taking into account the type II character of the structure, the quantum coupling effects, the spectral behavior of the SPV phase, and the photoluminescence spectra. As a result they have been attributed to optical transitions in the quantum dots and the wetting layers, respectively. The main mechanism for carrier separation in the SPV generation process is clarified via the analysis of the SPV phase spectra. The influence of the substrate absorption on the SPV spectra is discussed in details. V

show abstract

Acceptor levels in gallium arsenide (luminescence measurements)

Cited by 50 publications

References 8 publications

Phonon-assisted recombination in Fe-based spin LEDs

Phonon-assisted recombination in Fe-based spin LEDs

Temperature study of the photoluminescence of a single InAs/GaAs quantum dot

Optical properties of multi-layer type II InP/GaAs quantum dots studied by surface photovoltage spectroscopy

Contact Info

Product

Resources

About