diff --git a/requirements.txt b/requirements.txt
index 4586091..2f73f06 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,7 @@
+pip
 numpy
 matplotlib
 scipy
 plotly
 cython
-qutip
\ No newline at end of file
+qutip==4.4.0
\ No newline at end of file