diff --git a/notebook/lattice-vibration/Phonon_2D.ipynb b/notebook/lattice-vibration/Phonon_2D.ipynb
index 40e5fb5..f5645d0 100644
--- a/notebook/lattice-vibration/Phonon_2D.ipynb
+++ b/notebook/lattice-vibration/Phonon_2D.ipynb
@@ -94,22 +94,9 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 1,
+   "execution_count": null,
    "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "application/vnd.jupyter.widget-view+json": {
-       "model_id": "757123a79b524a27a3b714e45ca56cce",
-       "version_major": 2,
-       "version_minor": 0
-      },
-      "text/plain": []
-     },
-     "metadata": {},
-     "output_type": "display_data"
-    }
-   ],
+   "outputs": [],
    "source": [
     "import matplotlib.pyplot as plt\n",
     "%matplotlib widget\n",
@@ -129,7 +116,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 2,
+   "execution_count": null,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -142,7 +129,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": null,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -156,7 +143,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": null,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -208,7 +195,7 @@
     "for widget in widgets:\n",
     "    handler.widgetList.append(widget)\n",
     "\n",
-    "handler.tick_box_arrows.value = False\n",
+    "handler.tick_box_arrows.value = True\n",
     "handler.set_view_parameters(clipDist=1, quality=\"low\")\n",
     "# handler.slider_atom_radius.value = 0.1\n",
     "handler.slider_arrow_radius.value = 0.1\n",
@@ -357,26 +344,9 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 5,
+   "execution_count": null,
    "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "text/html": [
-       "<style>\n",
-       ".box_style{\n",
-       "    border : 2px solid red;\n",
-       "}\n",
-       "</style>\n"
-      ],
-      "text/plain": [
-       "<IPython.core.display.HTML object>"
-      ]
-     },
-     "metadata": {},
-     "output_type": "display_data"
-    }
-   ],
+   "outputs": [],
    "source": [
     "%%html\n",
     "<style>\n",
@@ -388,38 +358,9 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 6,
+   "execution_count": null,
    "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "application/vnd.jupyter.widget-view+json": {
-       "model_id": "e81610d2e290403b975766fbde9e578c",
-       "version_major": 2,
-       "version_minor": 0
-      },
-      "text/plain": [
-       "VBox(children=(Tab(children=(VBox(children=(GridBox(children=(VBox(children=(Output(),), layout=Layout(grid_ar…"
-      ]
-     },
-     "metadata": {},
-     "output_type": "display_data"
-    },
-    {
-     "data": {
-      "application/vnd.jupyter.widget-view+json": {
-       "model_id": "ce1aa41687f24701883503a9d28cd6e4",
-       "version_major": 2,
-       "version_minor": 0
-      },
-      "text/plain": [
-       "HBox(children=(NGLWidget(max_frame=60),), layout=Layout(align_items='center', display='flex', flex_flow='colum…"
-      ]
-     },
-     "metadata": {},
-     "output_type": "display_data"
-    }
-   ],
+   "outputs": [],
    "source": [
     "display(actions, HBox([handler.view], layout=layout).add_class(\"box_style\"))"
    ]