A high-temperature superconducting qubit implements a quantum mechanical two-level system. The high-temperature superconducting qubit comprises a first superconductor, a second superconductor, and an overlap region. The first superconductor comprises a first high-temperature superconductor material. The second superconductor comprises a second high-temperature superconductor material. In the overlap region, at least a first section of the first surface and at least a second section of the second surface overlap, the first section and the second section are arranged in parallel at a distance corresponding to a predefined distance, and the first orientation and the second orientation are arranged with an angle corresponding to a predefined angle. The high-temperature superconducting qubit comprises a Josephson junction between the first high-temperature superconductor material and the second high-temperature superconductor material. The Josephson junction provides the quantum mechanical two-level system of the high-temperature superconducting qubit.

The present disclosure describes non-classical (e.g., quantum) computing systems and methods that utilize dopant molecules contained in host materials as qubits.

A multiple functioning superconductive device was invented based on Toroidal Josephson Junction (FFTJJ) array with 3D-cage structure self-assembled organo-metallic superlattice membrane. The device not only mimics the structure and function of an activated Matrix Metalloproteinase-2 (MMP-2) protein, but also mimics the cylinder structure of the Heat Shock Protein (HSP60) protein, that works at room temperature under a normal atmosphere, and without external electromagnetic power applied. The device enabled direct rapid real-time monitoring atto-molarity concentration ATP in biological specimens and was able to define the anti-inflammatory and pro-inflammatory status revealed a transitional range of ATP concentration under antibody-free, tracer-free and label-free conditions.

A multiple functioning superconductive device was invented based on Toroidal Josephson Junction (FFTJJ) array with 3D-cage structure self-assembled organo-metallic superlattice membrane. The device not only mimics the structure and function of an activated Matrix Metalloproteinase-2 (MMP-2) protein, but also mimics the cylinder structure of the Heat Shock Protein (HSP60) protein, that works at room temperature under a normal atmosphere, and without external electromagnetic power applied. The device enabled direct rapid real-time monitoring atto-molarity concentration ATP in biological specimens and was able to define the anti-inflammatory and pro-inflammatory status revealed a transitional range of ATP concentration under antibody-free, tracer-free and label-free conditions.

A van der Waals capacitor and a qubit constructed with such a capacitor. In some embodiments, the capacitor includes a first conductive layer; an insulating layer, on the first conductive layer; and a second conductive layer on the insulating layer. The first conductive layer may be composed of one or more layers of a first van der Waals material, the insulating layer may be composed of one or more layers of a second van der Waals material, and the second conductive layer may be composed of one or more layers of a third van der Waals material.

Methods, systems and apparatus for forming Josephson junctions with reduced stray inductance. In one aspect, a device includes a substrate; a first superconductor layer on the substrate; an insulator layer on the first superconductor layer; a second superconductor layer on the insulator layer, wherein the first superconductor layer, the insulator layer, and the second superconductor layer form a superconductor tunnel junction; and a third superconductor layer directly on a surface of the first superconductor layer and directly on a surface of the second superconductor layer to provide a first contact to the superconducting tunnel junction and a second contact to the superconductor tunnel junction, respectively.

Methods, systems and apparatus for forming Josephson junctions with reduced stray inductance. In one aspect, a device includes a substrate; a first superconductor layer on the substrate; an insulator layer on the first superconductor layer; a second superconductor layer on the insulator layer, wherein the first superconductor layer, the insulator layer, and the second superconductor layer form a superconductor tunnel junction; and a third superconductor layer directly on a surface of the first superconductor layer and directly on a surface of the second superconductor layer to provide a first contact to the superconducting tunnel junction and a second contact to the superconductor tunnel junction, respectively.

A superconducting quantum mechanical device includes first, second, third and fourth Josephson junctions connected in a bridge circuit having first, second and third resonance eigenmodes. The device also includes first and second capacitor pads. The first and second capacitor pads and the bridge circuit form a superconducting qubit having a resonance frequency corresponding to the first resonance eigenmode. The device further includes first and second resonator sections. The first and second resonator sections and the bridge circuit form a resonator having a resonance frequency corresponding to the second resonance eigenmode. The device also includes a source of magnetic flux arranged proximate the bridge circuit. The source of magnetic flux is configured to provide, during operation, a magnetic flux through the bridge circuit to cause coupling between the first, second and third resonance eigenmodes when the third resonance eigenmode is excited.

Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a substrate and a quantum well stack disposed on the substrate. The quantum well stack may include a quantum well layer and a back gate, and the back gate may be disposed between the quantum well layer and the substrate.

Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a substrate and a quantum well stack disposed on the substrate. The quantum well stack may include a quantum well layer and a back gate, and the back gate may be disposed between the quantum well layer and the substrate.