I1z+I1mI2m+I2z+I2x

SpinDrops

SpinDrops is an interactive quantum spin simulator that uses the DROPS Representation to provide a rich visualization of spin system dynamics. The DROPS Representation is a general approach for the visualization of arbitrary spin operators, it is used to graphically fully illustrate spin system time evolution. SpinDrops is a powerful educational tool and pulse sequence visualizer.

SpinDrops (since version 2.0) is a project of the Glaser Group of the Chemistry Department at the Technical University of Munich (TUM). It is offered to the community for free. More information about the project, its goals, and history can be found under acknowledgments.

I1z+I2z+I3z

Fig. 1 The SpinDrops display of a 3-spin system and a simple pulse-delay experiment

With SpinDrops you can interactively explore spin dynamics by simply trying out different options and parameters. This website is organized as a book: chapters Tutorial, Feature Manual, Examples, and FAQ outline the concepts and use of the SpinDrops app, while chapters on Mathematical Background, DROPS Representation, Color Code and Physics provide background on the DROPS representation and spin physics. In addition, there are a number of Challenges to tackle!

Purpose

Some primary motivations for the creation of SpinDrops:

  • Actually see what is going on in an experiment.
  • Understand the properties of spin operators.
  • Develop intuition about the effects of pulse sequences.
  • Become familiar with standard experimental building blocks.
  • Invent and test novel pulse sequences.

Objectives

Some concepts from NMR that can be learned by working and playing with SpinDrops:

  1. Effects of non-selective and selective rotations on spin operators.
  2. Effects of frequency offsets and spin-spin couplings.
  3. How to use various experimental building blocks to manipulate the state of a spin system.
  4. Product operators (antiphase operators, multiple-quantum coherence, coherence order).
  5. Principles of polarization and coherence transfer.

Quickstart

SpinDrops is very flexible, and considerable effort has been put into making it easy to use. A typical approach to see the spin dynamics created by a given pulse sequence involves the following steps:

  • Select a spin system and its parameters (offset frequencies and coupling constants).
  • Choose the initial state of the spin system (e.g. z magnetization of spin I1).
  • Pick a pulse sequence (e.g. a 90° pulse followed by a delay).
  • Run the pulse sequence by pressing the play button ( ► ) and see the resulting time evolution in the DROPS display.

Spin System properties, such as spin offsets and couplings, can be modified by selecting Spin System ‣ Parameters….

The pulse sequence can be modified by double-clicking on the sequence display.

For more detailed information about using SpinDrops, please see the Tutorial and Feature Manual.

Todo

expand this quickstart