en.Wedoany.com Reported - Professor Zhou Miao, a national-level talent, chief scientist of a key national R&D program, and professor at Beihang University, explained in a popular science manner the core role of the quantum tunneling effect in modern industrial technology. Quantum tunneling refers to the quantum phenomenon where microscopic particles have a probability of directly penetrating a barrier even when their energy is insufficient to overcome it. This effect is a crucial physical foundation for semiconductors, microscopes, and precision electronic devices.
The characteristics of quantum tunneling include three aspects. First, particles can still "pass through walls" with insufficient energy; when the particle energy is lower than the barrier height, there is still a probability of penetration. The thinner the barrier and the smaller the energy gap, the higher the tunneling success rate. Second, tunneling is a probabilistic random event that cannot be precisely predicted; only the overall penetration probability can be statistically determined. Third, the tunneling process differs from classical motion; particles are observed on the other side of the barrier through wave function extension and probability distribution, without a continuous trajectory.
Tunnel diodes utilize the electron tunneling effect to achieve special conductive properties and were widely used in radios, voltage regulator circuits, and high-frequency switching components, serving as core components in early electronics. Scanning tunneling microscopes monitor current changes based on electron tunneling between the tip and the sample surface, enabling atomic-level surface imaging and advancing nanomaterials and condensed matter physics. Flash memory data erasure and writing rely on electron tunneling in the floating gate structure to complete charge migration, making large-capacity storage chips possible.
In the field of chip development, single-electron transistors based on controllable tunneling technology can leverage the controllable wall-penetrating ability of electrons to drive chip components toward smaller sizes, higher integration, and lower power consumption. In precision detection, tunneling current is extremely sensitive to changes in the external environment and can be used to manufacture ultra-high-precision non-invasive monitoring devices, flexible micro-sensors, and navigation devices that do not rely on GPS signals. In quantum computing, quantum tunneling is an important physical mechanism in some hardware components. By precisely controlling the timing and path of tunneling, it helps construct controllable quantum states and quantum devices, supporting improvements in the stability, controllability, and integration of quantum computing systems.
