  The low-temperature($4.2<T<12.5$ K) magnetotransport ($B<2$ T) of
two-dimensional electrons occupying two subbands (with energy $E_1$ and $E_2$)
is investigated in GaAs single quantum well with AlAs/GaAs superlattice
barriers. Two series of Shubnikov-de Haas oscillations are found to be
accompanied by magnetointersubband (MIS) oscillations, periodic in the inverse
magnetic field. The period of the MIS oscillations obeys condition
$\Delta_{12}=(E_2-E_1)=k \cdot \hbar \omega_c$, where $\Delta_{12}$ is the
subband energy separation, $\omega_c$ is the cyclotron frequency, and $k$ is
the positive integer. At $T$=4.2 K the oscillations manifest themselves up to
$k$=100. Strong temperature suppression of the magnetointersubband oscillations
is observed. We show that the suppression is a result of electron-electron
scattering. Our results are in good agreement with recent experiments,
indicating that the sensitivity to electron-electron interaction is the
fundamental property of magnetoresistance oscillations, originating from the
second-order Dingle factor.

Mesoscale and Nanoscale Physics