Planar qubits having increased coherence times

Patent metadata

Field	Value
Publication number	US-9818796-B2
Application number	US-201514616855-A
Country	US
Kind code	B2
Filing date	Feb 9, 2015
Priority date	Mar 4, 2013
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

An interdigitated capacitor includes a substrate and a pair of comb-like electrodes both formed on the semiconductor substrate and horizontally arranged thereon, each of the pair of comb-like electrodes including finger electrodes having a curved profile.

First claim

What is claimed is:

1. A method of operating a qubit, the method comprising:
beaming electromagnetic radiation on an interdigitated capacitor disposed in the qubit; and
taking measurements from the qubit during a coherence time of the qubit, wherein the qubit includes:
the interdigitated capacitor, including a substrate;
a pair of comb-like electrodes both formed on the semiconductor substrate and horizontally arranged thereon, each of the pair of comb-like electrodes including finger electrodes having a curved profile; and
a curved superconducting junction disposed on the substrate between the respective fingers of the pair of comb-like elements, and coupled to the interdigitated capacitor.

2. The method as claimed in claim 1 wherein the curved profile is a sinusoidal curve.

3. The method as claimed in claim 2 wherein the sinusoidal curve has a period and amplitude that determines a capacitance of the capacitor.

4. The method as claimed in claim 1 wherein the qubit further includes a bus line coupling a left set of the pair of comb-like electrodes.

5. The method as claimed in claim 1 wherein the qubit further includes a bus line coupling a right set of the pair of comb-like electrodes.

6. The method as claimed in claim 1 wherein the curved superconducting junction comprises a constant gap.

7. The method as claimed in claim 1 wherein the constant gap is 10 microns.

8. The method as claimed in claim 1 wherein the curved superconducting junction comprises a variable gap.

9. The method as claimed in claim 1 wherein the superconducting junction is physically positioned in between a right most finger electrode of all the finger electrodes in the left set of comb-like electrodes and a left most finger electrode of all the finger electrodes in the right set of comb-like electrodes, such that a left side of the superconducting junction is closer to the right most finger electrode in the left set of comb-like electrodes as compared to a left most finger electrode in the left set of comb-like electrodes and such that a right side of the superconducting junction is closer to the left most finger electrode in the right set of comb-like electrodes as compared to a right most finger electrode in the right set.

Assignees

• Globalfoundries Inc

Inventors

• Abraham David W
• Chow Jerry M

Classifications

• H01L28/88

  Electricity · mapped topic

• H01L28/82

  Electricity · mapped topic

• H01L27/18 Primary

  Electricity · mapped topic

• G06N99/002

  Physics · mapped topic

• H10D1/714

  having horizontal extensions · CPC title