Atomic spectra are defined as the spectrum of the electromagnetic radiation emitted or absorbed by an electron during transitions between different energy levels within an atom.

Quantum Computation III Atomic Spectra

Quantum Optics VII JaynesCummings Model
The JaynesCummings model (sometimes abbreviated JCM) is a theoretical model in quantum optics. It describes the system of a twolevel atom interacting with a quantized mode of an optical cavity (or a bosonic field).

Quantum Optics VI Quantization of Electromagnetic Field
Cavity quantum electrodynamics (cavity QED) is the study of the interaction between light confined in a reflective cavity and atoms or other particles, under conditions where the quantum nature of photons is significant.

Quantum Optics V Density Operator and Optical Bloch equations
Density Operator is a generalization of the more usual state vectors or wavefunctions: while those can only represent pure states, density matrices can also represent mixed states. Mixed states arise in quantum mechanics in two different situations: first when the preparation of the system is not fully known, and thus one must deal with a statistical ensemble of possible preparations, and second when one wants to describe a physical system which is entangled with another, without describing their combined state.

Quantum Optics IV Semiclassical description of matterlight interaction
Semiclassical description of matterlight interaction means that we shall present the fundamental features of the interaction of an atom, which will be treated quantum mechanically, with a classical electromagnetic field, that is an electromagnetic field described by real electric and magnetic vectors obeying Maxwell’s equations.

Quantum Optics III Twolevel system
In a calculation on a digital computer, information is processed in the form of socalled binary digits or bits, representing its smallest unit. Each bit can have the value 0 or 1, corresponding to two discrete states. Moving the processing of information itself into the quantum mechanical domain, one can identify a twolevel system now called quantum bit, or qubit that is based on two distinguishable quantum states. Therefore, it is necessary to look on twolevel system specifically.

Quantum Optics II Time dependent perturbation theory
In timedependent perturbation theory the main goal is to determine the timeevolution of a perturbed quantum system, with particular emphasis on calculating transition probabilities and modeling the irreversible decay of probability from a small quantum system coupled to a very large quantum system. The interaction picture will be used to discuss timedependent perturbation.

Quantum Optics I Rotating Frame Transformation
In timedependent perturbation theory the main goal is to determine the timeevolution of a perturbed quantum system, with particular emphasis on calculating transition probabilities and modeling the irreversible decay of probability from a small quantum system coupled to a very large quantum system. The interaction picture will be used to discuss timedependent perturbation.

Git 工作流
git 是一个分布式版本控制软件。

搭建代理服务器
回国后不能使用 ChatGPT，与其购买高端机场寄人篱下，不如自己租一个服务器作为代理来的省心和稳定。一般的机场提供的 IP 地址由于被多人共享使用，很容易被 ChatGPT 封锁，而自己租的私人服务器具有固定的 IP 地址，被墙后还可以重置，因此是更好的选择。本文演示如何在服务器上搭建 VLESS 节点并设置伪装。