Decoherence does not directly affect the probability of quantum tunneling. Decoherence refers to the process by which a quantum system interacts with its environment, leading to the loss of quantum coherence and the emergence of classical-like behavior. It causes the superposition of quantum states to "decohere" into classical mixtures, making the system behave as if it were in a definite state rather than a combination of states.
Quantum tunneling, on the other hand, is a distinct quantum mechanical phenomenon where a particle can pass through a potential barrier even when its energy is lower than the height of the barrier. This behavior is a consequence of the wave-like nature of particles and is described by the Schrödinger equation.
While decoherence can affect the overall behavior of a quantum system, such as suppressing interference patterns or leading to a loss of quantum information, it doesn't directly influence the probability of quantum tunneling. The probability of tunneling is determined by the properties of the barrier, the energy of the particle, and the quantum mechanical wave function describing the system.
It's worth noting that in some cases, decoherence can indirectly influence quantum tunneling. If the interaction with the environment is strong enough, it can modify the shape or characteristics of the potential barrier, thereby affecting the tunneling behavior. However, this is a more complex and specific scenario that depends on the details of the system and its environment. In general, decoherence and quantum tunneling are separate phenomena with distinct influences on quantum systems.