一个基于计数电子的电容标准
Keller1, Eichenberger, Martinis
1National Institute of Standards and Technology, Boulder, CO 80303, USA. National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
概括
一个新的电容标准使用单电子道来精确测量电容. 这种基于量子的方法实现了高精度,为电容量测量提供了自然标准.
科学领域:
- 计量学 计量学是一门学科.
- 量子电子学 量子电子学
- 电气工程 电气工程
背景情况:
- 准确的电容标准对于电力计量学至关重要.
- 现有的标准可能缺乏与基本物理常数的直接联系.
- 量子现象为新的,高度精确的测量标准提供了潜力.
研究的目的:
- 开发一个电容标准,直接基于电容的定义.
- 使用单电子道来实现精确的电荷转移.
- 建立一个基于量子的电容标准.
主要方法:
- 建造了一个冷电容器.
- 采用单电子道装置,以传输具有基本电荷 (e) 的已知数量的电子 (N).
- 测量了导致的电压变化 (ΔV),以确定电容 (C = Ne/ΔV).
主要成果:
- 在重复的电容量测量中达到0.3 x 10−6的相对标准偏差.
- 展示了基于基本电荷和电压测量实现电容的方法.
- 开发的标准显示了高精度和可重复性.
结论:
- 单电子道方法为电容标准提供了一个自然的基础.
- 这个量子标准类似于约瑟夫森效应用于电压和量子霍尔效应用于电阻.
- 这项工作通过提供基本电容标准来推进电力计量学领域.
相关概念视频
Capacitors and Capacitance
A device consisting of two electrical conductors that are separated by a distance and used to store electrical charges is called a capacitor. The space between the conductors is either a vacuum or an insulating material, called a dielectric. Capacitors have many applications, ranging from filtering static from radio reception to energy storage in heart defibrillators.
When the conductors are two identical parallel plates, it is called a parallel plate capacitor. When battery terminals are...
When the conductors are two identical parallel plates, it is called a parallel plate capacitor. When battery terminals are...
Equivalent Capacitance
Multiple capacitors can be connected in a circuit in series or parallel configuration. When the capacitor combination is connected to a battery, the potential drop across each capacitor and the magnitude of charge stored in the individual capacitor depends on the type of the connection. The capacitor combination is replaced by a single equivalent capacitor that stores the same amount of charge as the combination for a given potential difference.
The following strategies are adopted to calculate...
The following strategies are adopted to calculate...
Capacitors
Capacitors play a crucial role in car radios, where they filter and store frequencies to ensure clear signal reception. Essentially serving as energy storage devices, capacitors store energy within their electric field and are composed of two parallel conducting plates separated by a dielectric.
When a voltage source is connected to a capacitor, positive and negative charges accumulate on the opposite plates. This accumulation generates a potential difference that equals the product of the...
When a voltage source is connected to a capacitor, positive and negative charges accumulate on the opposite plates. This accumulation generates a potential difference that equals the product of the...
Energy Stored in Capacitors
A parallel plate capacitor, when connected to a battery, develops a potential difference across its plates. This potential difference is key to the operation of the capacitor, as it determines how much electrical energy the capacitor can store.
By integrating the equation that relates voltage and current in a capacitor, one can derive an equation for the voltage across the capacitor at any given time. This equation is crucial in understanding and predicting the behavior of capacitors in...
By integrating the equation that relates voltage and current in a capacitor, one can derive an equation for the voltage across the capacitor at any given time. This equation is crucial in understanding and predicting the behavior of capacitors in...
Equivalent Capacitance
From the study of resistive circuits, it is understood that employing a series-parallel combination serves as an effective strategy for simplifying circuits. Capacitors can be arranged within a circuit in one of two ways: a series configuration or a parallel configuration. The way these capacitors are connected to a battery will influence both the potential drop across each individual capacitor and the size of the charge that each capacitor can store. This is determined by the specific type of...
Applications of EMF Measurements
Electromotive force (EMF) measurements have a broad range of applications in various fields, including chemistry and physics. The electrochemical series, an arrangement of elements in order of their standard electrode potentials, can be determined through EMF measurements. Elements with lower standard potentials can reduce ions of elements with higher standard potentials.The standard cell potential, E°, allows for the calculation of the standard reaction Gibbs energy, ΔG°, and the equilibrium...


