To start off our second week at COSMOS we had one of our last lectures with Dr. Tu about semiconductors and their extreme importance to the optics and photonics industry, which was followed up by an introduction to PN junctions and laser diodes. After lunch we had a quantum cryptography lab set up with Dr. Sahar where a group randomly generated binary digits to act as a encryption kry to use to translate a 3 letter word into an encrypted word to be decrypted by another group.

Tuesday, Cluster 5 took another trip to Geisel to work on our ethics presentations in the morning. for our lab today Dr. Peter and the TA's prepared a double lab for us our first lab we used a photosensor to determine how certain levels of current allowed different light spreads which we measured to find the size of the chip emitting all of the light inside the laser diode . Our second lab we took diffraction gratings and looked through LED's to see their spectrum as well as learn about the properties of voltage and current in LED's compared to incandescent lights.

Our last lecture with Dr. Tu he finished talking about PN Junctions and laser diodes, after we wrapped up the last few topics he took his time giving us advice for the future. Soon after we left for our cluster field trip to Qualcomm, where we were given a tour around their museum where we learned about how many new technologies have roots that can be traced back to them, as well as getting to see their wall of patents and a special promotional board that had just arrived today to showcase their sponsoring of Manchester United. After the museum tour we had 2 professionals give us an in depth lecture on their current projects and the evolution of AI in fields like autonomous vehicles and large language models.

This morning we took our last trip to Geisel library to finish off our ethics presentations which would be due the next day. For our lab today we learned about different types of lenses and their respective uses in optics like Fresnel lenses which can be used to melt stuff like rocks with enough concentrated sunlight. Our lab today was to determine the focal point of a laser using different slides like a piece of tape or the letter E to examine the spread of light at different distances which we then measured the distance where the light was most concentrated and used it to find distances for a certain magnification ratio value in our case it was two.