Type-1.5 SNSPD: Interacting vortex theory of two bandgap superconducting single photon detectors
Year: 2025
Type: article
Abstract: Photon detectors based on type-2 superconductors have found widespread applications from on-chip quantum computing to quantum remote sensing. Here, we develop the theory for a different class of type-1.5 superconducting nanowire single photon detectors (SNSPDs) based on two bandgap superconductors with high transition temperatures such as MgB2 (Tc∼ 38.6 K). We show that vortex–vortex interactions in two component condensates lead to a unique operating regime where single photons can seed multiple vortices within a hotspot. We also show that dark counts are suppressed in the type-1.5 regime compared to the widely studied type-2 SNSPDs. Our work opens the door for exploring the unique vortex physics of two-gap superconductors for quantum device applications.
Source: Applied Physics Letters
DOI: 10.1063/5.0289611
Authors: Leif Bauer, Daien He, Sathwik Bharadwaj, Shunshun Liu, Prasanna V. Balachandran, Zubin Jacob
Institutions: Purdue University West Lafayette, University of Virginia
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Defense Sciences Office, DARPA
OpenAlex ID: W4414509751