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- In mesoscopic physics, ballistic conduction (ballistic transport) is the unimpeded flow (or transport) of charge carriers (usually electrons), or energy-carrying particles, over relatively long distances in a material. In general, the resistivity of a material exists because an electron, while moving inside a medium, is scattered by impurities, defects, thermal fluctuations of ions in a crystalline solid, or, generally, by any freely-moving atom/molecule composing a gas or liquid. Without scattering, electrons simply obey Newton's second law of motion at non-relativistic speeds. The mean free path of a particle can be described as the average length that the particle can travel freely, i.e., before a collision, which could change its momentum. The mean free path can be increased by reducing the number of impurities in a crystal or by lowering its temperature. Ballistic transport is observed when the mean free path of the particle is (much) longer than the dimension of the medium through which the particle travels. The particle alters its motion only upon collision with the walls. In the case of a wire suspended in air/vacuum the surface of the wire plays the role of the box reflecting the electrons and preventing them from exiting toward the empty space/open air. This is because there is an energy to be paid to extract the electron from the medium (work function). Ballistic conduction is typically observed in quasi-1D structures, such as carbon nanotubes or silicon nanowires, because of extreme size quantization effects in these materials. Ballistic conduction is not limited to electrons (or holes) but can also apply to phonons. It is theoretically possible for ballistic conduction to be extended to other quasi-particles, but this has not been experimentally verified. For a specific example, ballistic transport can be observed in a metal nanowire: due to the small size of the wire (nanometer-scale or 10−9 meters scale) and the mean free path which can be longer than that in a metal. Ballistic conduction differs from superconductivity due to the absence of the Meissner effect in the material. A ballistic conductor would stop conducting if the driving force is turned off, whereas in a superconductor current would continue to flow after the driving supply is disconnected. (en)
- Transporte balístico se refiere al transporte de electrones en un medio en el cual los electrones no son dispersados en él.Éste ocurre cuando el camino libre medio de los electrones es mucho mayor a la longitud que delimita el medio, en la direcciónen la que se propaga el electrón. Entonces éste medio no opone "resistencia" al paso del electrón, sin embargo, la conductividad no es infinita debido a que en un arregloexperimental el medio está conectado con el equipo de medición a través de contactos y por tanto aparece una resistencia debido a ellos. Es importante establecer que superconductividad y transporte balístico son dos fenómenos diferentes, en el caso del transporte balísticosi se quita la fuerza motriz que mueven los electrones desde un electrodo o contacto hacia el otro, los electrones dejarían de moversepor el medio; mientras que en un superconductor la corriente seguiría fluyendo aún en ausencia de esta fuerza motriz una vez que se haya establecido una corriente. (es)
- 弹道输运（Ballistic transport），是指介质中的电子在输运过程中几乎不会遇到散射。由于没有散射的作用，电子的运动仅遵从牛顿定律。 介质中的电阻一般是由电子散射而产生，这可以是因为、或者在平衡位置附近震荡的原子/分子引起的散射；也可以是由在气体和液体中自由运动的原子/分子引起的。 在介质中，我们可以定义一个自由程的概念，表示电子可以自由运动的路程。也就是说，在电子与其它物质发生碰撞，然后背离它初始运动方向之前它运动的路程。在很多情况下，我们可以通过减少杂质或者降低温度（当然，这个对半导体行不通）的办法来提高电子的自由程。 当电子的自由程（远）大于介质的尺度时，我们称此为弹道输运，这种情况下，电子只有碰到了边界才会改变运动方向。 (zh)
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- 弹道输运（Ballistic transport），是指介质中的电子在输运过程中几乎不会遇到散射。由于没有散射的作用，电子的运动仅遵从牛顿定律。 介质中的电阻一般是由电子散射而产生，这可以是因为、或者在平衡位置附近震荡的原子/分子引起的散射；也可以是由在气体和液体中自由运动的原子/分子引起的。 在介质中，我们可以定义一个自由程的概念，表示电子可以自由运动的路程。也就是说，在电子与其它物质发生碰撞，然后背离它初始运动方向之前它运动的路程。在很多情况下，我们可以通过减少杂质或者降低温度（当然，这个对半导体行不通）的办法来提高电子的自由程。 当电子的自由程（远）大于介质的尺度时，我们称此为弹道输运，这种情况下，电子只有碰到了边界才会改变运动方向。 (zh)
- In mesoscopic physics, ballistic conduction (ballistic transport) is the unimpeded flow (or transport) of charge carriers (usually electrons), or energy-carrying particles, over relatively long distances in a material. In general, the resistivity of a material exists because an electron, while moving inside a medium, is scattered by impurities, defects, thermal fluctuations of ions in a crystalline solid, or, generally, by any freely-moving atom/molecule composing a gas or liquid. Without scattering, electrons simply obey Newton's second law of motion at non-relativistic speeds. (en)
- Transporte balístico se refiere al transporte de electrones en un medio en el cual los electrones no son dispersados en él.Éste ocurre cuando el camino libre medio de los electrones es mucho mayor a la longitud que delimita el medio, en la direcciónen la que se propaga el electrón. Entonces éste medio no opone "resistencia" al paso del electrón, sin embargo, la conductividad no es infinita debido a que en un arregloexperimental el medio está conectado con el equipo de medición a través de contactos y por tanto aparece una resistencia debido a ellos. (es)
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- Conducció balística (ca)
- Ballistic conduction (en)
- Transporte balístico (es)
- 弹道输运 (zh)
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