Arrange tikzpicture horizontally

Question

I want to arrange three pictures drawn with tikzpicture horizontally. Unfortunately I can't make it work using any of the threads on a similar topic.

Thank you a lot for your help, best regards

Code:

\begin{figure}[!h]
 \centering
 \begin{subfigure}[b]{0.3\textwidth}

    \resizebox{\linewidth}{!}{
    \begin{tikzpicture}
    \draw plot[domain=-1.3:1.3]  ({\x,{(\x)^(2)+0.1*(\x)^(4)}});

    % Optional: Add axes
    \draw[-stealth] (-1.7,0) -- (1.7,0) node[right] {$M$};
    \draw[-stealth] (0,-1.7) -- (0,1.7) node[above] {${\cal L}$};

    \end{tikzpicture}
}
\caption{$T>T_c$}  
\end{subfigure}

\begin{subfigure}[b]{0.3\textwidth}

    \resizebox{\linewidth}{!}{
    \begin{tikzpicture}
    \draw plot[domain=-1.4:1.4]  ({\x,{0.5*(\x)^(4)}});

    %Optional: Add axes
    \draw[-stealth] (-1.7,0) -- (1.7,0) node[right] {$M$};
    \draw[-stealth] (0,-1.7) -- (0,1.7) node[above] {${\cal L}$};

    \end{tikzpicture}
}
\caption{$T=T_c$}  
\end{subfigure}

\begin{subfigure}[b]{0.3\textwidth}

    \resizebox{\linewidth}{!}{
    \begin{tikzpicture}
    \draw plot[domain=-1.6:1.6]  ({\x,{-2*(\x)^(2)+(\x)^(4)}});

    % Optional: Add axes
    \draw[-stealth] (-1.7,0) -- (1.7,0) node[right] {$M$};
    \draw[-stealth] (0,-1.7) -- (0,1.7) node[above] {${\cal L}$};

    \end{tikzpicture}
}
\caption{$T<T_c$}  
\end{subfigure}

\caption{Plot of the Landau free energy for different values $M$ and $t=\frac{T-T_c}{T_c}$ around criticality.\label{fig:phasetrans}}
\end{figure}