The photoluminescence (PL) spectrum of a two-dimensional electron gas (2DEG) at high magnetic fields has been a subject of intense research in the recent decade. The important ingredient, which distinguishes this problem from that of quantum Hall transport, is the presence of a photo-excited hole. We study the high magnetic field PL spectrum of a low-density (filling factor < 1) 2DEG at low temperatures (T=20 mK). Using a gated structure we follow the evolution of the spectrum from the dilute 2DEG limit into the higher density fractional quantum Hall (FQH) regime. We show that throughout this range the spectrum consists of singlet and triplet charged-excitons lines.
We also study the behavior of this system at larger filling factors >=1. A special emphasis is given to shake-up processes, in which the recombination is assisted by the creation of a magneto-plasmon or a spin-wave excitation.
- 1. G. Finkelstein, H. Shtrikman and I. Bar-Joseph
Mechanism
of shakeup processes in the photoluminesence of a two dimensional
electron gas at high magnetic fields.
Phys. Rev. B 56, 10326 (1997).
- 2. G. Finkelstein, H. Shtrikman and I. Bar-Joseph
Shake-up
processes of a two-dimensional electron gas in GaAs/AlGaAs quantum
wells in high magnetic fields.
Physica B 249-251, 575 (1998).
- 3. S. Glasberg, H. Shtrikman, and I. Bar-Joseph.
Optical
generation of spatially separated electron and hole gases in intrinsic
GaAs/AlGaAs double quantum wells
Phys. Rev. B 63, 113302 (2001).
- 4. S. Glasberg, H. Shtrikman, and I. Bar-Joseph. Photoluminescence
of a low-density two-dimensional hole gas in a GaAs quantum well:
Observation of valence-band Landau levels
Phys. Rev. B 63, 15 May (2001).
- 5. G. Yusa, H. Shtrikman, and I. Bar-Joseph
Charged-excitons
in the fractional quantum Hall regime
Submitted, Cond-Mat 0103561 (2001)
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