Related papers: Transmon qubit using Sn as a junction superconduct…
In this work, we study a series of tunable flux qubits inductively coupled to a coplanar waveguide resonator fabricated on a sapphire substrate. Each qubit includes an asymmetric superconducting quantum interference device which is…
Flux tuning of qubit frequencies in superconducting quantum processors is fundamental for implementing single and multi-qubit gates in quantum algorithms. Typical architectures involve the use of DC or fast RF lines. However, these lines…
Josephson junctions supply the nonlinear inductance element in superconducting qubits. In the widely used transmon configuration, where the junction is shunted by a large capacitor, the low charging energy minimizes the sensitivity of the…
Transmon qubits are ubiquitous in the pursuit of quantum computing using superconducting circuits. However, they have some drawbacks that still need to be addressed. Most importantly, the scalability of transmons is limited by the large…
This work presents a computational analysis of a superconducting transmon qubit design, in which the superconductor-insulator-superconductor (SIS) Josephson junction is replaced by a co-planar, superconductor-constriction-superconductor…
The reproducibility of qubit parameters is a challenge for scaling up superconducting quantum processors. Signal crosstalk imposes constraints on the frequency separation between neighboring qubits. The frequency uncertainty of transmon…
A superconducting transmon qubit resilient to strong magnetic fields is an important component for proposed topological and hybrid quantum computing (QC) schemes. Transmon qubits consist of a Josephson junction (JJ) shunted by a large…
Superconducting qubits are one of the most promising physical systems for implementing quantum computers. However, executing quantum algorithms of practical computational advantage requires further improvements in the fidelities of qubit…
The development of quantum circuits based on hybrid superconductor-semiconductor Josephson junctions holds promise for exploring their mesoscopic physics and for building novel superconducting devices. The gate-tunable superconducting…
We demonstrate a planar, tunable superconducting qubit with energy relaxation times up to 44 microseconds. This is achieved by using a geometry designed to both minimize radiative loss and reduce coupling to materials-related defects. At…
Superconducting qubits are solid state electrical circuits fabricated using techniques borrowed from conventional integrated circuits. They are based on the Josephson tunnel junction, the only non-dissipative, strongly non-linear circuit…
Superconducting qubits utilize the strong non-linearity of the Josephson junctions. Control over the Josephson nonlinearity, either by a current bias or by the magnetic flux, can be a valuable resource that brings tunability in the hybrid…
Materials improvements are a powerful approach to reducing loss and decoherence in superconducting qubits because such improvements can be readily translated to large scale processors. Recent work improved transmon coherence by utilizing…
We present an experimental study of nanowire transmons at zero and applied in-plane magnetic field. With Josephson non-linearities provided by the nanowires, our qubits operate at higher magnetic fields than standard transmons. Nanowire…
We introduce a simplified fabrication technique for Josephson junctions and demonstrate superconducting Xmon qubits with $T_1$ relaxation times averaging above 50$~\mu$s ($Q>$1.5$\times$ 10$^6$). Current shadow-evaporation techniques for…
We present a method for relieving aluminum 3D transmon qubits from a silicon substrate using micromachining. Our technique is a high yield, one-step deep reactive ion etch that requires no additional fabrication processes, and results in…
Quantum bits, or qubits, are an example of coherent circuits envisioned for next-generation computers and detectors. A robust superconducting qubit with a coherent lifetime of $O$(100 $\mu$s) is the transmon: a Josephson junction…
Superconducting quantum circuits provide a versatile platform for studying quantum materials by leveraging precise microwave control and utilizing the tools of circuit quantum electrodynamics (QED). Hybrid circuit devices incorporating…
As low-loss non-linear elements, Josephson junctions are the building blocks of superconducting qubits. The interaction of the qubit degree of freedom with the quasiparticles tunneling through the junction represent an intrinsic relaxation…
We report on long-term measurements of a highly coherent, non-tunable superconducting transmon qubit, revealing low-frequency burst noise in coherence times and qubit transition frequency. We achieve this through a simultaneous measurement…