JCM tutorial using QS Library

[Vanshaj0429]

Add Jaynes-Cummings Model Tutorial for Quantum Systems Library

Summary

This PR adds a detailed tutorial on the Jaynes-Cummings Model (JCM) that demonstrates the new quantum_systems library functionality from the dev.qsystem branch. The tutorial covers fundamental cavity quantum electrodynamics (QED) concepts with practical QuTiP implementations.

What's New

• Complete JCM tutorial (jc_tutorial.md) covering theory and practical implementation

• 5 detailed examples showcasing different system configurations:

  • Basic resonant system
  • Detuned system with dissipation
  • Rabi model (no rotating wave approximation)
  • System component access and analysis
  • Energy spectrum computation

• Advanced physics demonstrations:

  • Rabi oscillations and detuning effects
  • Dissipative dynamics with cavity/atomic decay
  • Thermal effects and steady-state analysis
  • Vacuum Rabi splitting spectroscopy

Technical Features

• Uses quantum_systems.jaynes_cummings() factory function for streamlined system construction
• Integrates seamlessly with QuTiP solvers (mesolve, spectrum, correlation_2op_1t)
• Demonstrates proper handling of:
  • Collapse operators for dissipation
  • Thermal bath effects
  • Parameter validation and defaults
  • Spectroscopic analysis methods

Educational Value

• Theoretical background: Historical context, mathematical formulation, and physical interpretation
• Practical implementation: Shows quantum systems library advantages over manual construction
• Real-world modeling: Includes dissipation, decoherence, and thermal effects
• Visualization: Multiple plots demonstrating key phenomena

Target Audience

• Students learning cavity QED and quantum optics
• Researchers adopting the new quantum systems library
• QuTiP users interested in streamlined system construction

Dependencies

This tutorial requires the dev.qsystem branch and will only work until that branch is merged with master.

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Author: Vanshaj Bindal
Branch: dev.qsystem (required)
File: JCM_Tutorial.md

[Vanshaj0429]

@nwlambert, can you have a look. I can streamline some of the stuff though, like section Using Jaynes-Cummings Factory Function have five small example, I can cut some of them down, if it's too much

[nwlambert]

Its looking good, I left a few comments. A little long, but I think thats good for this type of notebook. Good to add some basic tests right at the end, just a couple of things from the notebook that might not be caught by the usual qutip tests (e.g., maybe the spectrum stuff?) . Speaking of, we could probably get the tests running by editing

qutip-tutorials/.github/workflows/notebook_ci.yaml

Line 22 in ad896bb

qutip-branch: 'master'

to use the qsystem branch. but we would have to remember to change it back later!

[Vanshaj0429]

@nwlambert, I made the changes in the notebook. Seems alright to me now. I also changed branch in CI file. Please have a look

[nwlambert]

looking good, one minor typo, and then i think this is good from my POV

[Vanshaj0429]

@ajgpitch, @Ericgig, it passed the test😅

[Vanshaj0429]

@nwlambert, do you think it is merge ready?

[nwlambert]

yep, was just waiting in case there were any comments from the meeting on tuesday. guess not, will merge