Abe, Aritomi, Marc

Yesterday we removed the shinkosha evaluation plate and its holder from the translation stage.

We installed back the bulk reference sample and got R_bulk ~0.773 W/cm with

AC_bulkref = 0.0555 V;
DC_bulkref = 4.103 V;
P_in = 24.2e-3 W;
P_t = 11.7e-3 W;
abs_bulkref = 1.04;

Then, we brought the KASI sample inside the clean room and cleaned it with alcool while checking with the green light.

With this sample, the IU is now at z=43.1mm and the mirror centers are :

X_center = 327.5 mm

Y_center = 122.95 mm

Z_center = 62.5 mm (we had to increase the laser power to more than 1 W (~3W) to clearly see the phase change at the sample surfaces)

We added new X limit (lower vertical) on Zaber and started a circular map at Z_center with 2 cm radius.

Our initial guess of the absorption is abs~78 ppm/cm given by

AC = 2.3e-4 V;
DC = 4.242 V;
P_in = 3.24 W;
P_t = 2.77 W;
T_sample = P_t/P_in;
R_bulk = 0.7730 W/cm;
mat_correction=3.34;

abs = AC/(DC*P_in*sqrt(T_sample)*R_bulk)*1e6*mat_correction