Amplitude of Aharonov-Bohm oscillations in a small semiconductor ring interferometer in the tunneling regime

The amplitude g _AB of Aharonov-Bohm oscillations in a small semiconductor ring interferometer is studied as a function of the average conductance G _AV. Experimentally, it is found that, in the tunneling regime, the relative amplitude g _AB/G _AV of h/e oscillations is constant in the rings under investigation and smaller than unity. The small value of g _AB/G _AV in ring interferometers in the tunneling regime at low temperatures is explained by the difference in the amplitudes of the interfering electron waves.