English
Related papers

Related papers: Improved superconducting qubit coherence with high…

200 papers

The performance of state-of-the-art superconducting quantum devices is currently limited by microwave dielectric losses at different surfaces and interfaces. {\alpha}-tantalum is a superconductor that has proven effective in reducing…

Current state-of-the-art superconducting microwave qubits are cooled to extremely low temperatures to avoid sources of decoherence. Higher qubit operating temperatures would significantly increase the cooling power available, which is…

Quantum Physics · Physics 2024-08-19 Alexander Anferov , Shannon P. Harvey , Fanghui Wan , Jonathan Simon , David I. Schuster

Tantalum and aluminum on sapphire are widely used platforms for qubits of long coherent time. As quantum chips scale up, the number of Josephson junctions on Sapphire increases. Thus, both the uniformity and stability of the junctions are…

Superconductivity · Physics 2024-05-08 Yuzhen Zheng , Shuming Li , Zengqian Ding , Kanglin Xiong , Jiagui Feng , Hui Yang

This work is concerned with Al/Al-oxide(AlO$_{x}$)/Al-layer systems which are important for Josephson-junction-based superconducting devices such as quantum bits. The device performance is limited by noise, which has been to a large degree…

Quantum Physics · Physics 2020-01-07 S. Fritz , A. Seiler , L. Radtke , R. Schneider , M. Weides , G. Weiß , D. Gerthsen

The development of large-scale quantum processors benefits from superconducting qubits that can operate at elevated temperatures and be fabricated with scalable, foundry-compatible processes. Atomic layer deposition (ALD) is increasingly…

Magnetic-field-resilient superconducting circuits enable sensing applications and hybrid quantum-computing architectures involving spin or topological qubits and electro-mechanical elements, as well as studying flux noise and quasiparticle…

Quantum Physics · Physics 2022-03-15 J. Krause , C. Dickel , E. Vaal , M. Vielmetter , J. Feng , R. Bounds , G. Catelani , J. M. Fink , Yoichi Ando

We report a superconducting artificial atom with an observed quantum coherence time of T2*=95us and energy relaxation time T1=70us. The system consists of a single Josephson junction transmon qubit embedded in an otherwise empty copper…

We propose a superconducting qubit design, based on a tunable RF-SQUID and nanowire kinetic inductors, which has a dramatically reduced transverse electromagnetic coupling to its environment, so that its excited state should be metastable.…

Mesoscale and Nanoscale Physics · Physics 2013-10-22 Andrew J. Kerman

Quantum error correction will be an essential ingredient in realizing fault-tolerant quantum computing. However, most correction schemes rely on the assumption that errors are sufficiently uncorrelated in space and time. In superconducting…

We present a hybrid semiconductor-based superconducting qubit device which remains coherent at magnetic fields up to 1 T. The qubit transition frequency exhibits periodic oscillations with magnetic field, consistent with interference…

We present measurements and simulations of superconducting Nb co-planar waveguide resonators on sapphire substrate down to millikelvin temperature range with different readout powers. In the high temperature regime, we demonstrate that the…

The quasiparticle relaxation time in superconducting films has been measured as a function of temperature using the response of the complex conductivity to photon flux. For tantalum and aluminium, chosen for their difference in…

Superconductivity · Physics 2008-06-25 R. Barends , J. J. A. Baselmans , S. J. C. Yates , J. R. Gao , J. N. Hovenier , T. M. Klapwijk

We introduce a setup which realises a tunable engineered environment for experiments in circuit quantum electrodynamics. We illustrate this concept with the specific example of a quantum bit, qubit, in a high-quality-factor cavity which is…

Mesoscale and Nanoscale Physics · Physics 2013-06-14 P. J. Jones , J. A. M. Huhtamäki , J. Salmilehto , K. Y. Tan , M. Möttönen

As the field of superconducting quantum computing advances from the few-qubit stage to larger-scale processors, qubit addressability and extensibility will necessitate the use of 3D integration and packaging. While 3D integration is…

Quantum thermometry plays a critical role in the development of low-temperature sensors and quantum information platforms. In this work, we propose and theoretically analyze a hybrid circuit quantum electrodynamics architecture in which a…

Quantum Physics · Physics 2026-03-20 Shaojiang Zhu , Xinyuan You , Alexander Romanenko , Anna Grassellino

Developing fault-tolerant quantum processors with error correction demands large arrays of physical qubits whose key performance metrics (coherence times, control fidelities) must remain within specifications over both short and long…

Circuit quantum electrodynamics (cQED) experiments on superconducting qubit systems typically employ radiation shields coated in photon absorbing materials to achieve high qubit coherence and low microwave resonator losses. In this work, we…

Quantum Physics · Physics 2022-07-14 J. M. Kitzman , J. R. Lane , T. Stefanski , N. R. Beysengulov , D. Tan , K. W. Murch , J. Pollanen

We have developed a quantum annealing processor, based on an array of tunably coupled rf-SQUID flux qubits, fabricated in a superconducting integrated circuit process [1]. Implementing this type of processor at a scale of 512 qubits and…

Physical implementations of qubits can be extremely sensitive to environmental coupling, which can result in decoherence. While efforts are made for protection, coupling to the environment is necessary to measure and manipulate the state of…

Analog quantum simulations offer rich opportunities for exploring complex quantum systems and phenomena through the use of specially engineered, well-controlled quantum systems. A critical element, increasing the scope and flexibility of…

Quantum Physics · Physics 2018-08-09 M. Kounalakis , C. Dickel , A. Bruno , N. K. Langford , G. A. Steele