Hot-carrier energy-loss rates in GaAs/<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Al</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="normal">x</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Ga</mml:mi></mml:mrow><mml:mrow><mml:mn>1</mml:mn><mml:mi mathvariant="normal">−</mml:mi><mm

Leo, K.; Rühle, W. W.; Ploog, K.

doi:10.1103/physrevb.38.1947

Cited by 143 publications

(58 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The quantitative dependence of the effect on the well width, the carrier density, the phonon dispersion, and the carrier temperature have been briefly reviewed. Our research shows that the hot phonon effect leads to a substantial reduction in the ELR in high excitation and the hot phonon effect weakens slightly with a reduced dimensionality; however, the calculated reduction factor of the ELR solely due to the hot phonon effect is one order of magnitude less than the experimental value given by Leo et al [4], indicating that, in addition to the uncertainty in the experimental data, other factors which have been ignored or assumed in this investigation, such as the screening effect, the quasi-static approximation, the constant phonon lifetime † , etc. might be responsible for the discrepancy.…”

Section: Numerical Resultscontrasting

confidence: 61%

See 1 more Smart Citation

Numerical evaluation of energy loss rate for hot carriers in quantum wells

Zhu

Huang

Zhang

1998

Superlattices and Microstructures

View full text Add to dashboard Cite

Section: Numerical Resultscontrasting

confidence: 61%

“…This definition differs slightly from the experimentally measured data, which, defined as the ELR on low excitation density divided by the ELR measured [4], includes the effects of degeneracy, the screening of the carriers, as well as the hot phonon effect.…”

Section: Formalismmentioning

confidence: 93%

Numerical evaluation of energy loss rate for hot carriers in quantum wells

Zhu

Huang

Zhang

1998

Superlattices and Microstructures

View full text Add to dashboard Cite

“…Since the development of ultrafast lasers, numerous studies have been devoted to elucidating the photoexcited carrier dynamics by using nonlinear laser spectroscopic techniques such as optical pump and optical probe spectroscopy, four wave mixing, and transient gratings 1 . Time-resolved photoluminescence has also been used to investigate hot carrier relaxation and exciton formation [2][3][4] . With the development of mid-infrared ultrafast light sources, the wavelength of the optical probe has been extended to the lower energy region and it has become possible to access the intraband transitions, i.e., the free carrier responses, or the intra-exciton transitions with sub-ps temporal resolution.…”

Section: Introductionmentioning

confidence: 99%

Cooling dynamics of photoexcited carriers in Si studied using optical pump and terahertz probe spectroscopy

Suzuki

Shimano

2011

Phys. Rev. B

View full text Add to dashboard Cite

We investigated the photoexcited carrier dynamics in Si by using optical pump and terahertz probe spectroscopy in an energy range between 2 meV and 25 meV. The formation dynamics of excitons from unbound e-h pairs was studied through the emergence of the 1s-2p transition of excitons at 12 meV (3 THz). We revealed the thermalization mechanism of the photo-injected hot carriers (electrons and holes) in the low temperature lattice system by taking account of the interband and intraband scattering of carriers with acoustic and optical phonons. The overall cooling rate of electrons and holes was numerically calculated on the basis of a microscopic analysis of the phonon scattering processes, and the results well account for the experimentally observed carrier cooling dynamics. The long formation time of excitons in Si after the above-gap photoexcitation is reasonably accounted for by the thermalization process of photoexcited carriers.

show abstract

“…Knowing the theoretical curve dE/dt for a Boltzman distribution in the case of bulk GaAs [19,20] one can easily calculate the cooling curve by numerical integration with the only parameter T 0 . However in the case of QWs an ad hoc additional factor α > 1 is added dE/dt exper = dE/dt theor /α by which the measured energy-loss rate is reduced compared to the theoretical value [19,20,21]. Here we obtain a good fit for α = 2.9, see the bold line in Fig.…”

Section: Institut De Photonique Et Electronique Quantiques Ecole Polmentioning

confidence: 99%

Determination of the Exciton Formation in Quantum Wells from Time-Resolved Interband Luminescence

et al. 2004

View full text Add to dashboard Cite

We present the results of a detailed time resolved luminescence study carried out on a very high quality InGaAs quantum well sample where the contributions at the energy of the exciton and at the band edge can be clearly separated. We perform this experiment with a spectral resolution and a sensitivity of the set-up allowing to keep the observation of these two separate contributions over a broad range of times and densities. This allows us to directly evidence the exciton formation time, which depends on the density as expected from theory. We also evidence the dominant contribution of a minority of excitons to the luminescence signal, and the absence of thermodynamical equilibrium at low densities.PACS numbers: 71.35.Cc,71.35.Ee,73.21.Fg,78.47.+p,78.67.De Excitons in quantum wells form quite an appealing quasiparticle showing a large range of optical properties that have proven at the same time technologically useful, and physically interesting [1]. A large part of this interest is linked with the appearance of excitonic resonances in absorption up to room temperature. It is also well known, since the seminal work of Weisbuch et al [2], that free excitons appear to dominate the luminescence response of semiconductor quantum wells at low temperatures. Part of the origin of this effect lies in the breakdown of the translational symmetry which brings a very efficient recombination channel to free excitons in quantum wells [3,4].Interestingly, in the low density regime, time resolved luminescence (TR-PL) in quantum wells is observed to be always dominated by light coming at the exciton energy, even under non resonant excitation. The observations of this dominant contribution are so numerous that only a very partial list of references may be given here [5,6,7,8,9] (in order to be specific, we only consider here the case of quantum wells grown on GaAs substrates). A double question has then been debated for more than 10 years in the literature: first how do free electron hole pairs bind into excitons and second does indeed the luminescence at very short time proceed from bound excitons. A brief survey of the literature allows to find that experimentalists have reported formation times ranging from less than 10 ps up to about 1 ns [7,8,9, 10] and theoretical values range from 100 ps [11,12,13] to over 20 ns [14]. Clearly, the origin of this spreading in the reported values lies in the poor sensitivity of the experiments used in general to probe the exciton formation process, except for the case of the recent terahertz absorption experiments [10]. On the theoretical side, binding of an electron hole pair into an exciton requires, at low temperatures, the emission of an acoustic phonon, which brings long formation time due to the small coupling of acoustic phonons to excitons.The long formation time of excitons, together with the observation of luminescence at the exciton energy at the shortest times [7,15] led Kira et al [16] to introduce the idea that a free electron hole plasma, properly including Coulomb correla...

show abstract

Hot-carrier energy-loss rates in GaAs/AlxGa1−

Cited by 143 publications

References 42 publications

Numerical evaluation of energy loss rate for hot carriers in quantum wells

Numerical evaluation of energy loss rate for hot carriers in quantum wells

Cooling dynamics of photoexcited carriers in Si studied using optical pump and terahertz probe spectroscopy

Determination of the Exciton Formation in Quantum Wells from Time-Resolved Interband Luminescence

Contact Info

Product

Resources

About