This week with research, I added the piezoelectric materials (PM) to the oscillating thermal diode (OTD) for the first time. The materials arrived on Monday evening, so I mainly started to test them out on Tuesday. Also on Tuesday, I still had some remaining experiments from the different diode configurations from last week, so I finished those up. Those experiments went well since was able to clearly represent them in a graph and deduct which configurations were not effective. I also found the configuration with the fastest oscillation, which serves as a starting point when adding the PMs. 

With the PMs, I first used a multimeter to test their voltage output when I applied stress to them. The first issue was that the measurements were hard to read because the voltages spiked really fast, so I could not get a clear sense on how effective they were. The multimeter was sometimes maxed out whenever these voltage spikes. After talking with some of the graduate students in the lab, I built a circuit with a capacitor to charge it with a piezo by pressing it multiple times. I read the voltage on the capacitor to get a sense of what types of force or stress make the piezo work more effectively. This way, the measurements are more steady. I also used the accumulated charge to power an LED, which was fun.

After building that circuit,  I tried connecting the piezo to a different multimeter that connects to a computer, which has a program called LabVIEW. I am very new to this program and not everyone in the lab knows it super well either, so I had to learn mostly independently how to connect the multimeter to the computer to display data, which was a little bit of a challenge but I am glad I made it work. Now with this program, I can get voltage readings from the piezos on a graph, which helps me see how the voltage changes over time.

Once I felt confident about this setup, I did a quick test by adding a piezo disk to the oscillating thermal diode. I think it went pretty well. I did not get the fastest oscillations but they were relatively quick. However, I am facing many issues with the diode’s shuttle tilting, especially with the uneven surface of the piezo. This issue will likely be my focus for next week. I had fun applying these materials and seeing the voltage spikes on a graph.

I think one of the biggest highlights of week #3 was when I had my subgroup meeting. I improved in the the way I presented my weekly work to my PI. I found that slides helped me communicate more clearly and stay organized. My PI gave me good feedback based on the slides I prepared and said I am doing well, which makes me more confident compared to last time to last week. I am getting a good sense of what to discuss to feel less concerned. Essentially, I need to present my status and not worry about some maybe being slower than others, as it is normal. Additionally, this was my first week without my assigned mentor, but I think I’m doing well so far. The graduate students in my lab have been very helpful and friendly, which has helped me make progress more confidently.

I also noticed that I haven’t shared any pictures and I probably will regret it once I look back at these blog posts, so I will include some pictures here with some labels just for fun.