A quantum device (100) includes: an interposer (112); a quantum chip (111); a first connection part (130) that is provided between the interposer (112) and the quantum chip (111) and electrically connects a wiring layer of the interposer (112) to a wiring layer of the quantum chip (111); a predetermined signal line (w1) arranged in the wiring layer of the quantum chip (111); first shield wires (ws1) arranged in the wiring layer of the quantum chip (111) along the predetermined signal line (w1); a second shield wire (ws2) arranged in the wiring layer of the interposer (112); and a second connection part (150) that is provided between the interposer (112) and the quantum chip (111) so as to contact the first shield wires (ws1) and the second shield wire (ws2).

A circuit assembly for cooling a quantum electrical device, use of said circuit assembly, a system and a method for cooling a quantum electric device are provided. The circuit assembly comprises a quantum electric device to be cooled, at least one normal-metal-insulator-superconductor (NIS) tunnel junction electrically connected to the quantum electric device and at least one superconductive lead for supplying a drive voltage V.sub.QCR for said at least one NIS tunnel junction. The quantum electric device is cooled when the voltage V.sub.QCR is supplied to at least one NIS tunnel junction, said voltage V.sub.QCR being equal to or below the voltage NΔ/e, where N=1 or N=2, N is the number of NIS tunnel junctions electrically coupled in series with the means for generating the voltage, Δ is the energy gap in the superconductor density of states, and e is the elementary charge.

A magnetic Josephson junction (MJJ) device having a ferrimagnetic/ferromagnetic (FIM/FM) exchange-biased bilayer used as the magnetic hard layer improves switching performance by effectively sharpening the hysteresis curve of the device, thereby reducing error rate when the device is used in a Josephson magnetic random access memory (JMRAM) memory cell. Thus, the materials and devices described herein can be used to build a new type of MJJ, termed a ferrimagnetic Josephson junction (FIMJJ), for use in JMRAM, to construct a robust and reliable cryogenic computer memory that can be used for high-speed superconducting computing, e.g., with clock speeds in the microwave frequency range.

An active cooling structure, comprising a non-superconducting layer, a superconducting layer, and an array of Superconductor-Insulator-Normal Metal (NIS) tunnel junctions. The non-superconducting layer may comprise a plurality of non-superconducting traces. The superconducting layer may comprise a plurality of superconducting traces. The array of Superconductor-Insulator-Normal Metal (NIS) tunnel junctions may be located between the plurality of non-superconducting traces and the plurality of superconducting traces.

A quantum system includes a qubit array comprising a plurality of qubits. A bus resonator is coupled between at least one pair of qubits in the qubit array. A switch is coupled between the at least one qubit pair of qubits.

A method for improving lifetime and coherence time of a qubit in a quantum mechanical device is provided. The method includes providing a substrate having a frontside and a backside, the frontside having at least one qubit formed thereon, the at least one qubit having capacitor pads. The method further includes at least one of removing an amount of substrate material from the backside of the substrate at an area opposite the at least one qubit or depositing a superconducting metal layer at the backside of the substrate at the area opposite the at least one qubit to reduce radiofrequency electrical current loss due to at least one of silicon-air (SA) interface, metal-air (MA) interface or silicon-metal (SM) interface so as to enhance a lifetime (T1) and a coherence time (T2) in the at least one qubit.

A quantum device according to an example embodiment includes a quantum chip 10, and an interposer 20 on which the quantum chip 10 is mounted, in which the interposer 20 includes a conductive wiring line CL1 electrically connected to the quantum chip 10, a mounting surface 21 of the interposer 20 on which the quantum chip 10 is mounted or an opposite surface 22 opposite to the mounting surface 21 includes a first area AR11 and a second area AR12 different from the first area AR11 as viewed in a direction perpendicular to the mounting surface 21 or the opposite surface 22, the conductive wiring line CL1 is disposed in the first area AR11 on the mounting surface 21 or the opposite surface 22, and a movable member 60 is in contact with the second area AR12 of the interposer 20.

A digital circuit includes at least one quantum wire resonant tunneling transistor that includes an emitter terminal, a base terminal, a collector terminal, an emitter region in connection with the emitter terminal, a base region in connection with the base terminal, a collector region in connection with the collector terminal, an emitter barrier region between the emitter region and the base region, and a collector barrier region between the collector region and the base region. At least one of the emitter region, the base region, and the collector region includes a plurality of metal quantum wires.

A novel and useful quantum computing machine architecture that includes a classic computing core as well as a quantum computing core. A programmable pattern generator executes sequences of instructions that control the quantum core. In accordance with the sequences, a pulse generator functions to generate the control signals that are input to the quantum core to perform quantum operations. A partial readout of the quantum state in the quantum core is generated that is subsequently re-injected back into the quantum core to extend decoherence time. Access gates control movement of quantum particles in the quantum core. Errors are corrected from the partial readout before being re-injected back into the quantum core. Internal and external calibration loops calculate error syndromes and calibrate the control pulses input to the quantum core. Control of the quantum core is provided from an external support unit via the pattern generator or can be retrieved from classic memory where sequences of commands for the quantum core are stored a priori in the memory. A cryostat unit functions to provide several temperatures to the quantum machine including a temperature to cool the quantum computing core to approximately 4 Kelvin.

A method for processing a semiconductor device with two closely space gates comprises forming a template structure, wherein the template structure includes at least one sub-structure having a dimension less than the CD. The method further comprises forming a gate layer on and around the template structure. Then, the method comprises removing the part of the gate layer formed on the template structure, and patterning the remaining gate layer into a gate structure including the two gates. Further, the method comprises selectively removing the template structure, wherein the spacing between the two gates is formed by the removed sub-structure.