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  Ferromagnetic (FM) semiconductors oﬀer the prospect 
  of combining high-density storage and gate-controlled 
  logic in a single material. The realization of spin-valve 
  devices from FM semiconductors requires the controlled 
  switching of magnetization in adjacent layers between 
  antiferromagnetic (AFM) and FM conﬁgurations. This 
  has motivated several theoretical investigations of inter- 
  layer coupling in all-semiconductor devices1, and AFM 
  coupling has recently been demonstrated in (Ga,Mn)As 
  multilayers separated by p-type non-magnetic spacers2. 
  However, the Curie temperature TC of (Ga,Mn)As is 
  currently limited to 185 K in single layers3, and is 
  typically much lower for layers embedded within a 
  heterostructure2, which is an obstacle to the practical 
  implementation of semiconductor spintronics. 
  
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  Here, we demonstrate an antiferromagnetic coupling 
  and exchange bias in Fe/(Ga,Mn)As bilayer ﬁlms, by 
  combining element-speciﬁc XMCD measurements and 
  bulk-sensitive superconducting quantum interference de- 
  vice (SQUID) magnetometry. As with previous studies 
  of FM metal/FM semiconductor bilayers4,5 (and in con- 
  trast to AFM coupled FM metal/FM metal exchange bias 
  structures10,11) the layers are in direct contact without 
  a non-magnetic spacer in between. We distinguish in- 
  terface and bulk (Ga,Mn)As layers that are respectively 
  strongly and weakly antiferromagnetically coupled to the 
  Fe overlayer. In agreement with Ref.7, the interface layer 
  remains polarized at room temperature. 
  
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