diff --git a/DIRECTORY.md b/DIRECTORY.md
index 5c9cba5a461a..4f0e137a8148 100644
--- a/DIRECTORY.md
+++ b/DIRECTORY.md
@@ -1116,6 +1116,7 @@
   * [Center Of Mass](physics/center_of_mass.py)
   * [Centripetal Force](physics/centripetal_force.py)
   * [Coulombs Law](physics/coulombs_law.py)
+  * [Diffraction](physics/diffraction.py)
   * [Doppler Frequency](physics/doppler_frequency.py)
   * [Escape Velocity](physics/escape_velocity.py)
   * [Faraday Lenz Law](physics/faraday_lenz_law.py)
@@ -1479,7 +1480,6 @@
     * [Sol1](project_euler/problem_800/sol1.py)
 
 ## [Quantum](quantum)
-  * [Q Fourier Transform](quantum/q_fourier_transform.py)
   * [Shor Algorithm](quantum/shor_algorithm.py)
 
 ## [Scheduling](scheduling)
diff --git a/physics/diffraction.py b/physics/diffraction.py
new file mode 100644
index 000000000000..12a205bae07a
--- /dev/null
+++ b/physics/diffraction.py
@@ -0,0 +1,98 @@
+import math
+
+
+def check_min_intensity(
+    slit_width: float = 1.0, diff_angle: float = 0.0, wavelength: float = 100.0
+) -> bool:
+    """
+    Checks whether the intensity is at a minimum in a diffraction pattern.
+
+    Args:
+        slit_width: The width of the slit in millimeters.
+        diff_angle: The diffraction angle in radians.
+        wavelength: The wavelength of light in nanometers.
+
+    Returns:
+        True if minimum intensity is met; otherwise, False.
+
+    >>> check_min_intensity(4, 0.25, 300)
+    False
+    >>> check_min_intensity(1, 0.0001, 100)
+    True
+    """
+    wavelength *= 10**-6
+    n_val = round(slit_width * (diff_angle) / wavelength, 5)
+    r_val = n_val - math.floor(n_val) == 0
+    return r_val
+
+
+def check_max_intensity(
+    slit_width: float = 1.0, diff_angle: float = 0.0, wavelength: float = 100.0
+) -> bool:
+    """
+    Checks whether the intensity is at a maximum in a diffraction pattern.
+
+    Args:
+        slit_width: The width of the slit in millimeters.
+        diff_angle: The diffraction angle in radians.
+        wavelength: The wavelength of light in nanometers.
+
+    Returns:
+        True if maximum intensity is met; otherwise, False.
+
+    >>> check_max_intensity(1, 0.001, 100)
+    False
+    >>> check_max_intensity(1, 0.00005, 100)
+    True
+    """
+    wavelength *= 10**-6
+    n_val = round(((2 * slit_width * diff_angle) - wavelength) / (2 * wavelength), 4)
+    return n_val - math.floor(n_val) == 0
+
+
+def intensity_single_slit(
+    slit_width: float = 1.0, diff_angle: float = 0.0, wavelength: float = 100.0
+) -> float:
+    """
+    Computes the intensity for a single-slit diffraction pattern.
+
+    Args:
+        slit_width: The width of the slit in millimeters.
+        diff_angle: The diffraction angle in radians.
+        wavelength: The wavelength of light in nanometers.
+
+    Returns:
+        The intensity of the diffraction pattern.
+
+    >>> intensity_single_slit(1, 0.0005, 100)
+    0.9999999999177533
+    """
+    beta = math.pi * slit_width * (math.sin(diff_angle) / wavelength)
+    return (math.sin(beta) / beta) ** 2
+
+
+def intensity_double_slit(path_diff: float = 0, intensity_max: float = 1.0) -> float:
+    """
+    Computes the intensity for a double-slit diffraction pattern.
+
+    Args:
+        path_diff: The path difference in the two waves.
+        intensity_max: The maximum intensity.
+
+    Returns:
+        The intensity of the diffraction pattern.
+
+    >>> intensity_double_slit(0, 1)
+    4.0
+    >>> intensity_double_slit(0.001, 1)
+    3.999999000000084
+    >>> intensity_double_slit(0)
+    4.0
+    """
+    return 4 * intensity_max * (math.cos(path_diff / 2)) ** 2
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()