Polarized electron emission from a series of new strained short-period AlIn
GaAs/AlGaAs superlattices (SLs) is investigated. The In layer content was c
hosen to give minimal conduction band offset with large strain splitting of
the V-band. Simultaneous changing of Al content in both SL layers provides
variation of the structure band gap. We demonstrate that tuning of the SL
to the excitation energy can be achieved without loss of the electron polar
ization. The polarization of up to 84% was measured at room temperature. (C
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