Magneto-photoluminescence study on fractional quantum Hall effect in CdTe-CdMgTe modulation n-doped single quantum wells

Energy spectra of fractional quantum Hall systems in the presence of a valence hole

“…A number of experimental [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] and theoretical [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] studies of the optical properties of quasi-two-dimensional (2D) electron systems in high magnetic fields have been carried out in the recent years. In structures where both conduction electrons and valence holes are confined in the same 2D layer, such as symmetrically doped quantum wells (QW's), the photoluminescence (PL) spectrum of an electron gas (2DEG) involves neutral and charged exciton complexes (bound states of one or two electrons and a hole, X = e-h and X − = 2e-h).…”

“…24 The bi-layer systems are realized experimentally in heterojunctions and asymmetrically doped wide QW's, in which a perpendicular electric field causes separation of electron and hole 2D layers by a finite distance d. Unless d is smaller than the magnetic length λ, the PL spectra of bi-layer systems show no recombination from X − states. Instead, they show anomalies [1][2][3][4][5][6][7] at the filling factors ν = 1 3 and 2 3 , at which Laughlin incompressible fluid states 38 are formed in the 2DEG, and the fractional quantum Hall (FQH) effect 39 is observed in transport experiments.…”

Photoluminescence from fractional quantum Hall systems: Role of separation between electron and hole layers

“…The optical properties of quasi-two-dimensional (2D) electron systems in high magnetic fields have been extensively studied in the recent years both experimentally [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] and theoretically. [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] In symmetrically doped quantum wells (QW), where both conduction electrons and valence holes are confined in the same 2D layer, the photoluminescence (PL) spectrum of an electron gas (2DEG) probes the binding energy and optical properties of neutral and charged excitons (bound states of one or two electrons and a hole, X = e-h and X − = 2e-h), rather than the original correlations of the 2DEG itself.…”

“…24 Unless d is smaller than the magnetic length λ, the PL spectra of such bilayer systems show no recombination from X − states. Instead, they show anomalies [1][2][3][4][5][6][7] at the filling factors ν = 1 3 and 2 3 at which Laughlin incompressible fluid states 39 are formed in the 2DEG and the fractional quantum Hall (FQH) effect 40 is observed in transport experiments. The present paper is a continuation of our earlier work 29 where we studied the energy spectra of 2D fractional quantum Hall systems in the presence of an optically injected valence hole.…”

“…24 Unless d is smaller than the magnetic length λ, the PL spectra of such bilayer systems show no recombination from X − states. Instead, they show anomalies [1][2][3][4][5][6][7] at the filling factors ν = 1 3 and 2 3 at which Laughlin incompressible fluid states 39 are formed in the 2DEG and the fractional quantum Hall (FQH) effect 40 is observed in transport experiments.…”