Yes, even if the slit size is smaller than the wavelength of light, it will still exhibit diffraction. Diffraction is a phenomenon that occurs when waves encounter an obstacle or a slit and spread out into the region beyond the obstacle. It is a fundamental property of waves, including light waves.
The extent of diffraction depends on the size of the opening or obstacle relative to the wavelength of the waves. When the slit size is smaller than the wavelength of light, the diffraction effect is more pronounced, and the spreading of the light waves becomes more evident.
If the slit size is much smaller than the wavelength, the diffraction pattern will become more pronounced, and the light will spread out in a broader manner. This is commonly observed in experiments using narrow slits or small openings, such as the famous double-slit experiment. In such cases, the diffraction pattern displays interference fringes, indicating the wave-like behavior of light.
However, as the slit size decreases and approaches the scale of the wavelength or becomes comparable to it, the diffraction effects become more complex and intricate. At extremely small scales, the wave nature of light becomes less noticeable, and the behavior may start to resemble more particle-like interactions, such as scattering.
In summary, even if the slit size is smaller than the wavelength of light, diffraction will still occur. The magnitude and characteristics of the diffraction pattern will depend on the relative size of the slit to the wavelength, and the diffraction effects will be more pronounced when the slit size is smaller compared to the wavelength.