Work as an experimental physicist

Jun 18, 2015 research germanium

I got an Email from the Department of Marketing Communications & University Relations telling me that

We recently heard of the SDBOR grant you received for your research, “Development of a Segmented p-type Point-Contact High-Purity Germanium Detector for Rare-Event-Search Experiments” and wanted to congratulate you for this honor. A press release has already been created, but we are now looking to do a brief write-up to be posted on the school’s website in order to inform the public, since you have earned this grant and recognition for it. Would you be willing to provide a brief summary of this particular research and what you hope to accomplish with the grant?

The official news release entitled State Grants Advance Public University research can be found in the South Dakota State News. There is also a press release entitled 3 USD Faculty Among South Dakota Regents Research Grants Recipients from USD.

According to the official news release, 8 out of 30 proposals were funded this year. The funding rate is about 26%, which is pretty high. However, the funded projects are all from different disciplines, meaning that, on average, only one proposal would be funded for a specific discipline each year. I did a little bit of Google search and found that the PIs of the 8 funded projects are all assistant professors. I guess the reason is that senior faculties are competing federal funds and kindly leave this pie to new comers.

Here is a short summary of the project I proposed to do:

The principal investigator (PI) proposes to develop a segmented p-type point-contact high-purity germanium (Ge) detector to combine two of the most advanced Ge detector technologies, surface segmentation and point contact. The former provides rich information for background identification; the latter offers low energy threshold and excellent pulse shape discrimination power. The difficulty lies on the fact that the lithium-diffused outer surface of a p-type point-contact detector is too thick to segment. This problem can be solved by replacing the lithium-diffused surface with a surface sputtered with amorphous Ge, the thickness of which is only ~0.1 microns. The crystal for the proposed detector can be provided by the Ge crystal growth facility at the University of South Dakota (USD); the surface evaporation technique can be learned from the Lawrence-Berkeley National Laboratory; the segmentation scheme can be determined by a sophisticated Ge detector simulation package developed by the PI and his coworkers. Such a detector may become an attractive solution for next-generation dark matter and neutrinoless double beta decay experiments, well in line with the interests of both SURF and NSF. It is also a potential commercial product for radiation detection in industry or military, because of its sensitivity to low energy radiation and interaction positions. The proposed research activities will add Ge detector fabrication capacity on top of the already existing Ge crystal growth infrastructure at USD, and will produce valuable preliminary results to secure various external funds.

One can also find at the beginning of this post a short video explaining this idea in more detail.

To the general public, my project may be summarized as: I propose to develop a new type of germanium detector to detect dark matter particles and to study neutrino properties in underground laboratories. It combines two major germanium detector technologies and has the potential to become a commercial product for radiation detections in industry or military.

About

Blogs on physics research and educational activities of Jing LIU, an assistant professor in physics at the University of South Dakota. He is an experimental physicist developing novel particle detectors for astroparticle physics and civil use.