  We predict that in a narrow gap III-V semiconductor quantum well or a wire an
observable spin current can be generated with a time dependent gate to modify
the Rashba spin-orbit coupling constant. Methods to rectify the so generated AC
current are discussed. An all-electric method of spin current detection is
suggested, which measures the voltage on the gate in the vicinity of a 2D
electron gas carrying a time dependent spin current. Both the generation and
detection do not involve any optical or magnetic mediators.
