Raw data from a long distance Bell-inequality experiment
========================================================

Authors: Gregor Weihs, Christoph Simon, Thomas Jennewein, Harald
Weinfurter, and Anton Zeilinger

The data contained in the two archives alice.zip and bob.zip is 10
seconds from a series of experiments 1997-1999 performing a long
distance test of Bell's inequality and quantum key distributions
(Alice, west end of Innsbruck campus and Bob, east end of
campus). Publications that are based on the present data include
G. Weihs et al., Phys. Rev.  Lett. 81:5039 (1998) and T. Jennewein et
al. Phys. Rev. Lett. 85:4729 (2000).

In each archive there are three files. 

*_H.txt: Cryptic laboratory comments containing information about some
unimportant(?) experimental parameters.

*_V.dat: Photon arrival times where the "arm" time has already been
subtracted. IEEE-8bit double precision numbers in "Big Endian"-form
naturally sorted ascendingly. Actual time resolution is 0.1 ns, but
accuracy is only 0.5 ns.

*_C.dat: Apparatus setting and "outcome" for each photon detection
encoded in the following way: 16-bit integers in "Big Endian"-form,
each number showing the detector (0=vertical, 1=horizontal with repect
to the polarizer) that fired in its LSB and the position of the switch
(0=no rotation, 1=45 rotation) in the next to LSB. (Not very
efficient, but quicker when sampling directly to the PCs RAM during
data acquisition!) 

Somebody said that the bits must be reversed. I don't think so but
there is always a chance that we made double, compensating mistakes in
my LabView and C programming.

A detailed description of the experiment can be found on the webpages
of Anton Zeilinger's group in Vienna: http://www.quantum.at


Acknowledgements
----------------

The experiment yielding this data was mainly funded by the FWF
(Austrian Science Fund). G. W. was supported by the Austrian Academy
of Sciences. We acknowledge partial funding and facility support from
the University of Innsbruck.


Distribution
------------

The 10 s sequence of data in this archive may be used for teaching and
research purposes. They may be distributed as long as this file is
distributed alongside the data. 

We would, however, appreciate being notified of its use, contact
Gregor Weihs (University of Innsbruck, Austria and University of
Waterloo, Canada) or Anton Zeilinger (University of Vienna, Austria).

Copyright (C) 2003 Gregor Weihs and Anton Zeilinger
