We have studied exciton complexes such as charged excitons and biexcitons in dilute magnetic semiconductor Cd 1Àx Zn x Te/Cd 1ÀxÀy Zn x Mn y Te (x ¼ 0:07, y ¼ 0:43) quantum wells (well widths 4 and 9 nm). Laser excitation power dependence and time-resolved photoluminescence (PL) showed unique features related to excitons, charged excitons, and biexcitons. Four-wave-mixing spectroscopy with different choices of polarized incident light exhibited beating signals arising from exciton-biexciton interaction. Circular polarized PL was measured in magnetic fields of up to 42 T using a pulse magnet. The observed Zeeman splitting and the degree of circular polarization in magnetic fields revealed that the formation of biexcitons is quenched upon applying a magnetic field, and PL from the charged excitons was preserved up to the highest magnetic field.

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