No, quantum tunneling does not occur in USB sticks in the conventional sense. Quantum tunneling is a quantum mechanical phenomenon where particles can pass through energy barriers that, according to classical physics, they should not be able to penetrate.
In the context of USB sticks or other electronic devices, the term "quantum tunneling" is sometimes used metaphorically to describe the transfer of electrons through a thin insulating layer, such as a barrier or a potential well. This transfer is based on the principles of quantum mechanics, but it is not the same as the quantum tunneling phenomenon itself.
In USB sticks, data is stored in non-volatile memory, typically in the form of flash memory. Flash memory uses a different mechanism called "electronic tunneling" or "tunneling electron transfer" to move electrons between different states within the memory cells. This process relies on the principles of quantum mechanics, but it is not the same as the quantum tunneling phenomenon described earlier.
In flash memory, the memory cells contain transistors that can be programmed to store data by trapping or releasing electrons in a floating gate. The movement of electrons between the floating gate and the surrounding materials occurs through a process known as tunneling. However, this electronic tunneling does not involve the quantum tunneling of particles through energy barriers in the same way that is observed at the quantum level.
So, while the term "quantum tunneling" is sometimes used in a loose sense to describe certain electronic processes in devices like USB sticks, it is not the same as the quantum tunneling phenomenon described in quantum mechanics. The electronic tunneling in USB sticks is a classical process that relies on quantum principles but does not involve the same fundamental quantum effects observed at the atomic or subatomic scale.