Subband renormalization in dense electron-hole plasmas inIn0.53Ga0.47

Abstract

In 0.53 Ga 0.47 As/InP quantum wires have been investigated by cw high-excitation luminescence spectroscopy. Quantum-wire states up to the edge of the InP conduction band have been populated in the dense neutral electron-hole plasma. Up to three lateral subband transitions are clearly observed in the luminescence spectra. By using calculated line shapes, the temperature and the density of the e-h plasma as well as the band-gap reduction of the different lateral subbands have been determined. We observe a clear dependence of the renormalization on the subband index, which is traced to the density dependence of the exchange energy.

Influence of strain and quantum confinement on the optical properties of InGaAs/GaAs V-groove quantum wires

“…We indeed observed a reduction of the blueshift ͑Ͻ2 meV͒ when decreasing the QWR thickness to t eff Ͻ10 nm, in agreement with previous reports on thin InGaAs/AlGaAs V-groove QWRs. 24 However, contradictory observations and confused interpretations on the peak energy shift at high density for various strained QWR systems have been published in the literature, ranging from a sizable redshift ͑10 meV͒, 41 to virtually no shift, 21,24 on to a sizeable blueshift ͑25 meV; 42 17 meV͒. 12 We should thus be cautious with our interpretation, due to the many other phenomena occurring in this system at high excitation density such as band filling, excitonic correlations, band gap renormalization, and disorder.…”

Franz-Keldysh effect and dynamical Franz-Keldysh effect of cylindrical quantum wires

“…Moreover, in contrast to the twodimensional and three-dimensional cases, the Sommerfield factor is less than unity for all frequencies above the band gap. With rapid advance in material growth technology, both experimental [31][32][33][34][35] and theoretical [36][37][38][39][40][41] studies on semiconductor quantum wires are receiving renewed interest. These studies are important not only for elucidating the fundamental physics of one-dimensional semiconductors, but also for device applications of quantum wires.…”

Band-Gap Renormalization in Quasi-One-Dimensional Systems

“…This situation is somewhat different tha.n the ca.se in 2D systems, where the Ch term a.pproxima.tes the ba.nd-gap renor ma.liza.tion satisfactorily for the relevant density regime. [ 15] On the other ha.nd, a. recent work [6] on InGa.As/InP quantum wires made use of the un screened exchange energy (Ha.rtree-Fock) only to account for the subband renorma.lizations.…”

“…Within the sa.me spirit, we ca.lcula.te the renormalized total chemical potential of the electron-hole plasma. using (6) in which kp = rr N /2 is the Fermi wa.ve vector. The self-energy pa.rt in the a.hove expression is a.lso ea.lied the excha.nge-correla.tion contribution µxc to the chemical potential.…”

“…Recent progress in the fabrication techniques such as molecular-beam epitaxy (MBE) and lithographic de position have made possible the realization of such quasi-one-dimensional systems. [2] Band-gap renormalization as well as various optical properties of the QlD electron-hole systems have been studied [3,4,5,6,7] similar to the bulk (3D ) and quantum-well (2D ) semiconductors [8,9,10,11] where generally good agreement with the corresponding measurements [12] exist.…”