Microsoft Technology Licensing, LLC

Northrop Grumman Systems Corporation

James Matthew Murduck

Thomas F Ambrose

Melissa G Loving

A memory cell is provided that comprises a first superconductor electrode, a second superconductor electrode, and a magnetic Josephson junction (MJJ) stack disposed between the first superconductor electrode and the second superconductor electrode. The MJJ stack includes a magnetic reference layer and a magnetic storage layer. The memory cell further comprises a magnetically stabilizing structure disposed between the MJJ stack and the second superconductor electrode, wherein the magnetic stabilizing structure magnetically couples with the magnetic reference layer to strengthen the fixed state of the magnetic reference layer.

Magnetically stabilized magnetic Josephson junction memory cell

Superconducting circuits and memories that use a magnetic Josephson junction (MJJ) device as a pi inverter are disclosed. The MJJ device includes superconducting layers configured to allow a flow of a supercurrent through the MJJ device. The MJJ device further includes a magnetic layer arranged between the superconducting layers, where the magnetic layer has an associated magnetization direction, and where the first state of the MJJ device corresponds to a zero-phase of a supercurrent flowing through the MJJ device and the second state of the MJJ device corresponds to a &#x3c0;-phase of the supercurrent flowing through the MJJ device. In response to an application of a magnetic field, without any change in the magnetization direction of the magnetic layer, the MJJ device is configured to switch from the first state to the second state responsive to a change in a phase of the supercurrent.

Using a magnetic Josephson junction device as a pi inverter

Magnetic Josephson junction driven flux-biased superconductor memory cell and methods are provided. A memory cell may include a magnetic Josephson junction (MJJ) superconducting quantum interference device (SQUID) comprising a first MJJ device and a second MJJ device, arranged in parallel to each other, where the MJJ SQUID is configured to generate a first flux-bias or a second flux-bias, where the first flux-bias corresponds to a first direction of current flow in the MJJ SQUID and the second flux-bias corresponds to a second direction of current flow in the MJJ SQUID. The memory cell may further include a superconducting metal-based superconducting quantum interference device (SQUID) including a first Josephson junction (JJ) and a second JJ, arranged in parallel to each other, where each of the first JJ and the second JJ has a critical current responsive to any flux-bias generated by the MJJ SQUID.

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Ellicott City, MD, United States of America

James Matthew Murduck