Research in the field of transitions from insulators to metals discovered non-compliance in the traditional formula of the Landau-Zener. This discovery has offered new approaches to understanding resistance switching, which could have potential use in microelectronics and neuromorphic calculations.
The Mysterious Transitions from Insulator to Metal
When exploring most materials at the subatomic level, they can be classified as either metals, such as copper and iron which conduct electricity, or insulators, such as glass and rubber which do not. However, insulators have the potential to transform into metals under the influence of an intense electric field, presenting opportunities for microelectronics and super calculations. Despite this, the physics behind this phenomenon is not yet fully understood.
According to Professor Zhong Khan, the lead author of the study, the Landau-Zener formula has been used since the 1930s as a model to determine the necessary size of the electric field. However, subsequent experiments have revealed that materials require an electric field 1000 times smaller than what was previously evaluated by this formula. Khan stated, “So there is a huge discrepancy, and we need the best theory.”
To tackle this issue, Khan decided to investigate what happens when the electrons are already in the upper zone of the insulator. Through computer modeling, it was discovered that a relatively small electric field can cause the gap between the lower and upper zones to collapse, creating a quantum path for electrons to move up and down between the zones.
This new idea not only helps resolve inconsistencies in the Landau-Zener formula but also suggests the possibility of simultaneous electronic and thermal switching.
The findings of this study could be critical for areas such as neuromorphic calculation. Professor Jonathan Bird, Chairman of the Department of Electrical Engineering, believes that “the phenomena disclosed in these materials can ultimately serve as the basis of new microelectronic technologies, such as compact memorable devices for use in intensive applications such as artificial intelligence.”
Following the publication of the article, Khan plans to continue researching in this area. The path ahead involves a significant amount of work to clarify the conditions for the emergence of a quantum avalanche.