  In large data centers, storage nodes are organized in racks, and the
cross-rack transmission dominates the bandwidth cost. For the repair of single
node failures, codes achieving the tradeoff between the storage redundancy and
cross-rack repair bandwidth are called rack-aware regenerating codes (RRCs). In
this work, we give the first explicit construction of RRCs with the minimum
repair bandwidth (i.e., the cross-rack bandwidth equals the storage size per
node). Our construction applies to all admissible parameters and has the lowest
sub-packetization level. Moreover, the underlying finite fields are of size
comparable to the number of storage nodes, which makes our codes more
implementable in practice. Finally, for the convenience of practical use, we
also establish a transformation to convert our codes into systematic codes.
