Alp Sipahigil (Advisor)

Research advised by BSAC Co-Director Alp Sipahigil

Sipahigil Group:  List of Projects | List of Researchers

BPN966: Cryogenic Fiber Coupling for Silicon Quantum Photonics

Polnop Samutpraphoot
Lukasz Komza
Mutasem Odeh
Milena Mathew
Myung-Ki Kim
2022

We introduce a method for achieving high-efficiency and broadband fiber interfaces to silicon photonic devices at cryogenic temperatures, utilizing edge coupling between waveguides and lensed fibers. We will describe the simulation, design, and fabrication of single-sided waveguides featuring Bragg mirrors and tapered mode converter optimized for maximum photon collection from emitters in the devices. We then present fabrication techniques, including deep etching for edge coupling, as well as the experimental setup used to test our devices at cryogenic temperatures. Our method will...

BPN975: Suppressing Surface Piezoelectricity in Superconducting Circuits

Eric Li
Kadircan Godeneli
2022

Superconducting quantum circuits are one of the leading technologies for building quantum computers. These circuits are made of superconducting resonators with quality factors on the order of $10^5-10^6$. Because of the high device Q-factor when operating in the superconducting regime, loss mechanisms that would otherwise be insignificant to the overall resonator Q-factor start to become important. One such mechanism we explore in this project is the impact of surface piezoelectricity on qubit and resonator quality factors. Surface piezoelectricity arises due to atomic dipoles...

Eric Li

Alumni
Electrical Engineering and Computer Sciences
Professor Alp Sipahigil (Advisor)
B.S. 2022

Kadircan Godeneli

Graduate Student Researcher
Electrical Engineering and Computer Sciences
Professor Alp Sipahigil (Advisor)
Ph.D. 2026 (Anticipated)
Kadircan received his B.S. degrees in Electrical Engineering and Physics from Bogazici University, Istanbul, Turkey in 2021. He is currently pursuing a Ph.D. in the Quantum Devices Group at UC Berkeley under the supervision of Prof. Alp Sipahigil.