The behavior of a single photon is governed by the principles of quantum mechanics, which describe the behavior of particles at the atomic and subatomic levels. Refraction, on the other hand, is a macroscopic phenomenon that occurs when light passes through a boundary between two different media and changes its direction due to the change in the speed of light.
When it comes to a single photon, the concept of refraction becomes less straightforward because it involves the interaction of the photon with the surrounding medium. The behavior of a single photon passing through a medium is typically described by wave-particle duality, where it can exhibit both wave-like and particle-like characteristics.
In quantum mechanics, the path of a single photon is described by a probability wave function. This wave function describes the likelihood of finding the photon at different positions in space. When a photon interacts with a boundary between two media, its wave function undergoes a change, and there is a probability for the photon to be transmitted or reflected.
While a single photon does not strictly "refract" in the same way as a bulk beam of light, it can still undergo a change in direction and interact with the medium it is passing through. The specific behavior of a single photon interacting with a boundary depends on the nature of the medium and the properties of the photon, such as its energy and wavelength.
In summary, the behavior of a single photon passing through a medium is more accurately described by the principles of quantum mechanics, including wave-particle duality and probability wave functions. While a single photon does not exhibit refraction in the same way as a beam of light, it can still undergo changes in direction and interact with the medium it encounters.