Today I checked the bulk reference and got : R_bulk = 0.7527 cm/W (note that in this case I moved the IU by 0.32 mm)

With laser diode current of 6A I set up the HWP so to have P_in = 7.072W.

Using the DC values drop, the Kasi sample center positions are : X_center = 329.62 mm and Y_center = 122.81 mm.

The Zaber limits have been changed accordingly with some margin to check the incident power from remote.

I did a long Z scan and used the phase transition to get the center Z position at Z_center = 64.1 mm.

I realigned the DC at this position and started a circular map in the XY plane with parameters :

X = X_center, Y=Y_center, Z =Z_center, 20 mm radius, 0.1 mm step size, 500 ms waiting time, median/average filter order 5 and sensitivity = 5mV (ie 5 nA).

Preliminary absorption is : 75 ppm/cm (coherent with previous measurement)

with :

AC =4.6e-4 V
DC = 4.144 V
P_in = 7.074 W
P_t = 6.096 W
T_sample = P_t/P_in;
mat_correction=3.34;

All measurements should be finished tomorrow.