An individual photon is a quantum particle and exhibits both wave-like and particle-like characteristics, depending on how it is observed and measured. Here are some key aspects of an individual photon wave:
Wave-particle duality: Photons can exhibit properties of both particles and waves. When observed as particles, they are localized entities with discrete energy and momentum. However, when observed as waves, they exhibit wave-like characteristics such as interference and diffraction.
Momentum uncertainty: Like other quantum particles, photons have momentum uncertainty. This uncertainty arises from the wave-particle duality. It means that the momentum of a photon cannot be precisely determined at a given moment. Instead, there is a range of possible momentum values with associated probabilities.
Interference and diffraction: Photons can interfere with themselves and exhibit diffraction patterns. This behavior is characteristic of waves and is observed when photons pass through narrow slits or encounter obstacles. The interference and diffraction patterns result from the superposition of different possible paths that the photon can take.
Quantum superposition: Two individual photons created by the same source at different times are generally considered independent particles. Each photon has its own wave function, and their properties, such as polarization, direction, and momentum, can be different. However, in some cases, such as in entangled photon pairs, the quantum state of one photon can be correlated with the other, leading to non-local effects.
Phase through obstacles: Photons can exhibit a phenomenon called tunneling, where they can pass through barriers that would be classically impossible to penetrate. The probability of a photon tunneling through an obstacle depends on various factors, including the barrier's thickness, the energy of the photon, and the shape of the barrier potential. However, it's important to note that tunneling is a probabilistic phenomenon, and individual photons may or may not tunnel through obstacles.
In summary, an individual photon wave can exhibit wave-particle duality, interference, diffraction, momentum uncertainty, and the ability to tunnel through obstacles. While two photons created by the same source at different times are generally considered independent, there are cases where their quantum states can be correlated.