相关实验视频
Updated: Jul 5, 2025

06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
9.0K
对使用连贯和不连贯驱动器的开放式两量子比特系统的诺伊曼的控制
Oleg V Morzhin1, Alexander N Pechen1
1Department of Mathematical Methods for Quantum Technologies & Steklov International Mathematical Center, Steklov Mathematical Institute of Russian Academy of Sciences, 8 Gubkina Str., 119991 Moscow, Russia
Entropy (Basel, Switzerland)
|January 22, 2024
概括
研究人员开发了控制量子系统·诺伊曼 (S) 的方法. 这项研究通过在两量子比特系统中管理脱凝率,使得量子状态的精确操纵成为可能.
科学领域:
- 量子信息科学 量子信息科学
- 量子控制理论 量子控制理论
- 开放的量子系统 开放的量子系统
背景情况:
- 了解和控制量子状态对于量子技术至关重要.
- ·诺伊曼量化了量子状态的不确定性或混合性.
- 开放的量子系统经历了脱节,影响了它们的动态和可控性.
研究的目的:
- 开发一种方法来操纵一个开放的两量子比特系统的·诺伊曼.
- 探索各种控制目标,包括最小化,最大化,目标转向和状态约束满足.
- 调查连贯和不连贯的控制对动态的影响.
主要方法:
- 利用由戈里尼-科萨科夫斯基-苏达尔珊-林德布拉德主方程描述的马科维动力学.
- 适应了一步和两步梯度投影方法进行优化.
- 采用基因算法来解决控制挑战.
主要成果:
- 成功地调整了优化算法,以在时间依赖的脱凝合下操纵·诺伊曼.
- 证明了各种操纵目标 (最小化,最大化,目标方向,约束满足) 的数值结果.
- 展示了结合连贯和不连贯控制的有效性.
结论:
- 拟议的方法为控制开放的两量子比特系统的提供了一个强大的框架.
- 适应的数值方法对于实现特定的操纵目标是有效的.
- 这项工作有助于量子状态工程和控制的进步.
相关概念视频
Entropy Change in Reversible Processes
2.5K
In the Carnot engine, which achieves the maximum efficiency between two reservoirs of fixed temperatures, the total change in entropy is zero. The observation can be generalized by considering any reversible cyclic process consisting of many Carnot cycles. Thus, it can be stated that the total entropy change of any ideal reversible cycle is zero.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
2.5K
Entropy and the Second Law of Thermodynamics
2.8K
The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
2.8K
Conservation of Energy in Control Volume
842
Consider a turbine operating under steady-flow conditions. The control volume is drawn around the turbine, with fluid entering at one point and exiting at another. The turbine extracts energy from the fluid, which performs mechanical work (shaft work).
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
842
Open and closed-loop control systems
753
Control systems are foundational elements in automation and engineering. They are broadly categorized into open-loop and closed-loop systems. These classifications hinge on the presence or absence of feedback mechanisms, significantly influencing the system's performance, complexity, and application.
An open-loop control system operates without feedback from the output. It consists of two primary elements: the controller and the controlled process. The controller receives an input signal...
An open-loop control system operates without feedback from the output. It consists of two primary elements: the controller and the controlled process. The controller receives an input signal...
753
Entropy
30.2K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
30.2K
Entropy and Solvation
7.1K
The process of surrounding a solute with solvent is called solvation. It involves evenly distributing the solute within the solvent. The rule of thumb for determining a solvent for a given compound is that like dissolves like. A good solvent has molecular characteristics similar to those of the compound to be dissolved. For example, polar solutions dissolve polar solutes, and apolar solvents dissolve apolar solutes. A polar solvent is a solvent that has a high dielectric constant (ϵ...
7.1K

