IP Library › Granted Patent US 12,414,483
Granted Patent B2
US 12,414,483 · App. 17/469,380 · Granted Sep 9, 2025

Fabrication of normal conducting or low-gap islands for downconversion of pair-breaking phonons in superconducting quantum circuits

Inventors: Robert McDermott (Madison, WI); Britton Plourde (Jamesville, NY)
Assignees: WISCONSIN ALUMNI RESEARCH FOUNDATION; SYRACUSE UNIVERSITY
H10N69/00G06N10/40H10N60/0912H10N60/12
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Quick Facts
Patent No.
US 12,414,483
App. No.
17/469,380
Granted
Sep 9, 2025
Kind
B2
Abstract

Disclosed herein is a quantum processor comprising a substrate, a qubit structure formed on the substrate, an electroplated phonon downconversion material, and furrows through the electroplated phonon downconversion material forming a plurality of electroplated phonon downconversion islands coupled to the substrate configured to channel deposited energy away from the qubit structure. Also disclosed are methods of making and using the same.

Claims (7)

1. A quantum processor comprising a substrate, a qubit structure formed on the substrate, a phonon downconversion material, and furrows through the phonon downconversion material forming a plurality of phonon downconversion islands coupled to the substrate configured to channel deposited phonon energy away from the qubit structure,

wherein the phonon downconversion material is a normal metal or a superconductor having a lower energy gap than the superconductor used to form a Josephson junction in the quantum processor.

2. The quantum processor of claim 1 , wherein the furrows are formed by mechanical furrowing through the phonon downconversion material.

3. The quantum processor of claim 1 further comprising a seed layer positioned between the substrate and the phonon downconversion material.

4. The quantum process of claim 3 , wherein the furrows are formed by mechanical furrowing through the phonon downconversion material and the seed layer.

5. The quantum processor of claim 3 , wherein the seed layer comprises a bilayer of two different materials, wherein the layer adjacent to the phonon downconversion material is composed of the same material as the phonon downconversion material.

6. The quantum processor of claim 1 , wherein the phonon downconversion material is an phonon downconversion material, or is deposited on the substrate by vacuum sputtering or evaporation.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 22, 2021
From: MCDERMOTT, ROBERT
To: WISCONSIN ALUMNI RESEARCH FOUNDATION
Reel/Frame 057873/0710 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 22, 2021
From: PLOURDE, BRITTON
To: SYRACUSE UNIVERSITY
Reel/Frame 057891/0688 →
Continuity (1)
Related Publication 20230077178A1 · Mar 9, 2023
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