deletions | additions       diff --git a/In_order_to_better_read__.tex b/In_order_to_better_read__.tex  index 3805c05..ba72202 100644  --- a/In_order_to_better_read__.tex  +++ b/In_order_to_better_read__.tex 
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In order to better read the signals coming out from the photodiode (?), we applied a lock-in amplifier. A  Lock-in amplifier, also known as phase sensitive amplifier, is a powerful AC voltmeter. It only picks up frequencies that are around the reference frequency. In this way, when the wavelength of our laser drifts away a little bit, the lock-in amplifier can fix this unexpected change. (NOT SURE-SHOULD ASK HIM) WHITE NOISE?