\section{Results and discussion}

\begin{figure}[t,scale=2]
\begin{center}\leavevmode
\includegraphics[width=0.75\linewidth]{fig1a.eps}
\caption{ 
Magnetoresistance at different temperatures for the field $H_{\bot}$ 
applied perpendicular to the film plane. 
}\label{fig1}\end{center}\end{figure}
\par 
The object of investigation was
La$_{1-\mathrm{x}}$Ca$_{\mathrm{x}}$MnO$_{3}$ film with $\mathrm{x}
\approx 1/3$ ($\approx 120$~nm thick) which was grown on LaAlO$_{3}$ 
substrate by pulsed-laser deposition. 
The Curie temperature of the film was about 260 K. The MR behavior
for the magnetic fields applied perpendicular ($H_{\bot}$) and
parallel ($H_{\|}$) to the film plane is shown in Figs. 1 and 2 (in
both cases the magnetic field $\mathbf{H}$ was perpendicular to the
current).  At increasing of $H_{\bot}$ the MR is first negative (at
$H_{\bot} \leq 4$~kOe), then positive (4 kOe $\leq H_{\bot} \leq
12$~kOe), and then negative again. At increasing of $H_{\|}$ the MR
is positive below $H_{\|} \simeq 6$~kOe and negative above it. The
anisotropic behavior of this kind occurs only at low temperatures.
At $T > 20$~K the MR is negative for both directions of magnetic
field (Figs.1 and 2). Besides, we found that in the liquid-helium 
temperature range the resistance depends on
angle $\theta$ between $H_{\|}$ and current $I$ approximately in the
following way: $R({\theta})/R(0) = 1 + b\sin^{2}\theta$, where $b >
0$.
\par
The observed puzzling behavior of MR anisotropy is undoubtedly
connected with some interplay of different competing anisotropy
energies in the film studied (shape, strain-induced and intrinsic 
magnetocrystalline anisotropy energies). Besides, the surface and inner
layers of ferromagnetic film may have different anisotropy
properties, that can lead in some cases to canted magnetization and to a 
reorientation of spontaneous magnetization with varying the temperature
or magnetic field\cite{usadel}. The influence of the angle between 
current and magnetization can also give a substantial contribution. 
Taking all these into account and particularly the possible bilayer 
magnetic structure of ferromagnetic film\cite{usadel} it is possible to 
justify the observed results. The precise $\mathbf{M}(T,\mathbf{H})$ 
measurements are needed however to validate any  
particular explanation. We plan to do this.  
\par
We thank S.R. Surthi and R.K. Pandey for film preparation. Support at
TAMU was provided by the Robert A. Welch Foundation (Grant No. A-0514) and the
Texas Advanced Research Program (Grant No. 010366-003).  BIB and DGN acknowledge support
by NATO Scientific Division (Collaborative Research Grant No. 972112).

\begin{figure}[btp]
\begin{center}\leavevmode
\includegraphics[width=0.75\linewidth]{fig2a.eps}
\caption{ 
Magnetoresistance at different temperatures for the field $H_{\|}$ 
applied parallel to the film plane. 
}\label{fig2}\end{center}\end{figure}

