Engineering topics

Kutsaev, Sergey

Publications and source records attributed to Kutsaev, Sergey.

3 records

DOE OSTI2024

Nb$^{3}$Sn Technology for Low-beta linacs

Nb3Sn is the most advanced potential successor for niobium in superconducting RF accelerator cavities. Nb3Sn has a significantly higher critical temperature (18.3 K) compared to that of niobium (9.2 K). This has a large effect on the BCS surface resistance, and therefore, on the dynamic RF losses at 4.5 K. The higher critical temperature allows two important changes for cavity and cryomodule design. First, the lower BCS losses allow the designer to use a higher frequency, translating to physically smaller cavities and cryomodules. Second, the low dynamic losses allow the use of stand-alone cryocoolers instead of complex helium refrigerators and distribution systems. Fabrication of a prototype 218 MHz cavity, test results, and continuing challenges are discussed.

43 PARTICLE ACCELERATORS↗

DOE OSTI2024

Niobium-tin as a transformative technology for low-beta linacs

Niobium-tin has been identified as the most promising next-generation superconducting material for accelerator cavities. This is due to the higher critical temperature (Tc = 18 K) of Nb3Sn compared to niobium (TC = 9.2 K), which leads to greatly reduced RF losses in the cavity during 4.5 K operation. This allows two important changes during cavity and cryomodule design. First, the higher Tc leads to negligible BCS losses when operated at 4.5 K, which allows for a higher frequency to be used, translating to significantly smaller cavities and cryomodules. Second, the reduced dissipated power lowers the required cryogenic cooling capacity, meaning that cavities can feasibly be operated on 5-10 W cryocoolers instead of a centralized helium refrigeration plant. These plants and distribution systems are costly and complex, requiring skilled technicians for operation and maintenance. These fundamental changes present an opportunity for a paradigm shift in how low-beta linacs are designed and operated. Fabrication challenges and first coated cavity test results are discussed.

43 PARTICLE ACCELERATORS↗

DOE OSTI2024

Quantum computing structures and resonators thereof

Embodiments disclosed herein include a resonator for use in quantum computing. The resonator can include a housing that is disposed along a resonator axis. The housing can have a first portion extending from a housing distal end to near a qubit location and a second portion extending from near the qubit location to a housing proximal end. The housing can define a cavity extending from a cavity proximal end to a cavity distal end along a portion of the resonator axis. The housing can include a protrusion extending axially from the housing distal end along the resonator axis to near the qubit location. A proximal portion of the protrusion can include a tapered portion. The resonator can include a qubit extending into the cavity at the qubit location.

Kutsaev, Sergey↗