This folder contains the data presented in: D. P. Sadler et al., "Radiation trapping in a dense cold Rydberg gas"



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Figure 1(a&b): (experiment schematic and example high density spectrum)

(a) Schematic - no data provided. 
(b) Example high density excitation spectrum - see information for figure 2(d) (below) for details. 

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Figure 1(c&d): (probe beam attenuation and Rydberg populaiton distribution)

The model outputs preseneted in figure 1 (c) & (d) are given in the Matlab file "figure1c&d.mat".  

- The array titled "position_x" gives the position along the x-axis.  
- Figure 1(c): The array titled "probe_s" gives the probe beam saturation parameter at the position coresponding to the value in "position_x".  
   Column 1 is for optical depth = 3 (solid red line), 
   column 2 is for optical depth = 6 (dashed-dotted blue line), 
   column 3 is for optical depth = 14 (dotted purple line).  
- Figure 1(d): The array titled "Rydberg_fraction" gives the Rydberg excitation fraction at the position coresponding to the value in "position_x".  
   Column 1 is for optical depth = 3 (solid red line), 
   column 2 is for optical depth = 6 (dashed-dotted blue line), 
   column 3 is for optical depth = 14 (dotted purple line).  

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Figure 2: (density spectra)
Files are in folder Fig2.  

The data presented in the figure are given in the Matlab file "figure2_spectra_data.mat".  The values for the data are contained in the arrays with appropriate titles (e.g. "detuning", "N", "dN", "Q", "dQ", "b" and "db").  Each array has four columns corresponding to the four optical depts in the figure.  For example the data for figure 2(a) is given in column one of each array, 2(b) is in column two and so on...

The optical depth, b, of the various plots is given in array "b". The standard error on the optical depth measurement is in array "db". 

The fits from the models are in the Matlab file "figure2_spectra_model.mat".  The values are contained in the arrays with appropriate titles (e.g. "Detuning", "narrowfeature" and "pedestal").  The values are arranged in columns one to four as before.  

SUMMARY:
Left-hand column of figure 2:
Data: detuning is in array "detuning", <N> is in array "N", standard error of <N> is in array "dN". 
Model of narrow feature: detuning is in array "Detuning", line shape is given in array "narrowfeature". 
Model of pedestal: detuning is in array "Detuning", line shape is given in array "pedestal". The "narrowfeature" and "pedestal" are added together to give the overall profile shape.  

Right-hand column of figure:
Data: detuning is in array "detuning", Q is in array "Q", standard error on Q is in array "dQ". 

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Figure 3(a): (evolution with optical depth)

The data and fits for figure 3(a) are given in Matlab file "figure3a.mat".  

The data for the narrow feature (blue diamonds) are in array "cohvsb", where column one gives the b values, column two gives the <N>_Max values and column 3 gives the standard error on <N>_Max.  

The data for the pedestal feature (red squares) are in array "pedhvsb", where column one gives the b values, column two gives the <N>_Max values and column 3 gives the standard error on <N>_Max.  

The fit for the narrow feature (upper purple solid line) is given in arrary "satcurve", where column one gives the b values and colum two gives the <N>_Max values.  

The fit for the pedestal feature (lower red solid line) is given in arrary "OBEmodel_fit", where column one gives the b values and colum two gives the <N>_Max values.  

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Figure 3(b): (spatial profile)

The data and profiles for figure 3(b) are given in Matlab file "figure3b.mat".  

The data points are in array "data".  The first column is the y position, the second column is the <N> value, and the third column is the standard error on <N>.  

The shaded area showing the atomic density distribution is in the array "density_profile", where the first colum is the y position and the second column represents the atomic density.  

The output from the propagation model (solid purple line) is in array "propagation_model", where the first colum is the y position and the second column is the <N> calcualted from the model.  

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Figure 4(a&b): (spectra at times tau=0.6us and tau=4us)

The data presented in figures 4(a) and 4(b) are given in the Matlab file "figure4a&b_data.mat".  The detuning is in array "detuning".  The mean number of ion counts <N> are in the arrays "N_06" and "N_4", and the standard errors are in "SE_06" and "SE_4" for tau=0.6us and tau=4us respectively.  

The fits are in the Matlab file "figure4a&b_fits.mat".  The detuning is in array "Detuning".  The pedestal fits in arrays "Pedestal_06" and "Pedestal_4", and the overall fits are in arrays "OBEplusPedestal_06" and "OBEplusPedestal_4" for tau=0.6us and tau=4us respectively.  

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Figure 4(c): (N_max vs tau)

The data presented in figure 4(c) are given in the Matlab file "figure4c_data.mat".  The different arrays correspond to the different datasets:
"narrow" = <N>_max for the narrow component of the spectra,
"pedestal" = <N>_max for the pedestal component of the spectra,
"low_density" = <N>_max for the low density spectra.  

The arrays have the following structure:
column 1 = tau,
column 2 = <N>_max,
column 3 = stansard error on <N>_max.  

The trend lines presented in figure 4(c) are given in the Matlab file "figure4c_fits.mat".  The different arrays correspond to the different dataset fits:
"narrow_fit" = fit to <N>_max for the narrow component of the spectra,
"pedestal_fit" = fit to <N>_max for the pedestal component of the spectra,
"low_density_fit" = fit to <N>_max for the low density spectra, 
"MonteCarlo" = Monte Carlo model for <N>_max for the narrow component of the spectra.  

The arrays have the following structure:
column 1 = tau,
column 2 = <N>_max. 

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Figure 4(d): (Sectra from Monte Carlo simulations) 

The normalized model profiles presented in figure 4(d) are given in the Matlab file "figure4d.mat".  The detuning is in array "detuning".  The profiles are in the arrays "N_5E9", "N_5E10" and "N_5E11", which correspond to the model outputs for the densities 5 x 10^9 cm^-3, 5 x 10^10 cm^-3 and 5 x 10^11 cm^-3 respectively.  

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