Fig. 3.
Magnetic field dependence of PL. a Magnetic field dependent PL of X0 and XX0 in circular co-polarised and b cross-polarised configurations, for σ− excitation. The fine-structure lines are indicated as XX01 and XX02. The emission of XX0 brightens with increasing emission energy. X0 is displayed for reference. c Magnetic field dependent PL of XX− in a circular co-polarised configuration, for σ− excitation. In a, b and c the colour scale is linear. d Zeeman shift in the PL spectrum of X0 (filled black circles), XX0 (filled red and pink circles for the two components of the fine-structure) and XX− (filled blue circles). The double arrow is a scale bar of 2.5 meV. e PL intensity ratio of circular co-polarisation with opposite helicity I(σ-/σ-)/I(σ+/σ+) for X0, XX01 + XX02 and XX− as a function of magnetic field