CCE2 CCPQ project
=================

This code is intended to calculate the decoherence of central 
spin systems entangled with a bath of spin impurities using CCE2
formalism.

***Last modified version 23/02/2015***

CCE2 - Fortran library for spin decoherence
===========================================

Solves for the many-body dynamics of a central spin system coupled to
an interacting spin bath.

*To be implemented soon*
- Includes the generation of a crystal structure.
- Includes special methods for decoherence of electron/nuclear qubits.
- Includes sequence of CPMG pulses.

- Includes the decoherence using CCE2 method.

Installation
============

Requirements:

- Intel or GNU fortran compiler
- Git
- Make/Cmake

The following instructions are for a Unix-like environment
without root privileges.

In a terminal,

```sh
mkdir CCE2
cd CCE2
git clone https://github.com/UCLGuichard/CCE2
```

This gets the code. Now let's build it.

```sh
mkdir ./build
cd ./build
cmake ..
make
```

If all went well, you should now have created an executable CCE2.exe in 
the ./bin directory.

You may wish to modify the CMakeLists.txt to adapt to your own system.

***CCE2 has been tested on Linux***

Usage
-----

Run the executable CCE2.exe in the ./bin directory.
It takes the arguments defined in the input files 

basis.inp      ! Sets the properties of the system.

in the ./input folder. Modify them for your own purposes.

Testing
-------

*To be implemented soon.*

Example
-------

Getting help
------------

Documentation
=============

Requirements:

- Dot (contained in Graphviz package)
- LaTeX compiler (pdflatex)

You can generate a full documentation of CCE2 by using doxygen with the
Doxyfile:

doxygen Doxyfile

This will produce both an html call tree and a LaTeX documentation in the
doc directory.

License
=======

See LICENSE file for more details.

Citation
========

See CITATION file for more details.

Version
=======

1.0 (in progress)

History
=======

CCE2 is based on bits and pieces of old code for certain spin baths
and central spin systems. These were written by R. Guichard starting
in 2015. Methods used to efficiently fill Hamiltonian matrix elements
were originally written in Fortran by Prof. Tania Monteiro. Checking has
been performed with Setrak Balian's C++ spindec code:

http://www.bitbucket.org/sbalian/spindec

Acknowledgements
================

- Prof. Tania Monteiro
- Setrak Balian

Contact
=======

[Roland Guichard] - <r.guichard@ucl.ac.uk>