WordPress shortcut with jquery load function

Hello,
I have a page template that load with no problem my mat_data.php file

<?php
get_header(); ?>
<script type="text/javascript">
	jQuery(document).ready(function($){
  		$('.mat_id').click(function(){
    			var id = $(this).attr("id").substring(7);
			$("#testehugo").load("/wp-content/themes/twentythirteen-child/mat_data.php", {mat_ID: id});
		});
	});
</script>

	<div id="primary" class="content-area">
		<div id="content" class="site-content" role="main">

			<div class="entry-content" style="margin-top:30px; margin-bottom:30px">
				<div id="div_mat">
					<?php global $wpdb;
					$mats = $wpdb->get_results( "SELECT ID_Car, Brand, Model FROM wp_cars WHERE ID_User = ". $current_user->ID );

					foreach ( $mats as $mat )
					{
						?><div id="mat_id_<?php echo $mat->ID_Car;?>" class="mat_id">
						  <span class="car_name"><?php echo $mat->Brand;?> - <?php echo $mat->Model;?></span><br>
						  <?php echo $mat->ID_Car;?>
						</div><?php
					}
					?>
				</div>
				<div id="testehugo">
					<?php include('mat_data.php'); ?>
				</div>
				<?php the_content(); ?>
			</div><!-- .entry-content -->

		</div><!-- #content -->
	</div><!-- #primary -->

<?php //get_sidebar(); ?>
<?php get_footer(); ?>

mat_data.php:

<div id="teste_mat_user">
    <?php
		echo do_shortcode('[wpdatatable id=1 var1='.($_REQUEST["mat_ID"]).']');
    ?>
</div>

The problem is that when I reload div class mat_id by clicking it, I get 500 (Internal Server Error)
Is there some issue with shortcodes and load function?

Thanks for the help