Publications associées à Critical Josephson current in the dynamical Coulomb blockade regime

Mechanically induced correlated errors on superconducting qubits with relaxation times exceeding 0.4 ms

Tobias Kippenberg, Amir Youssefi, Xuxin Wang, Mahdi Chegnizadeh, Shingo Kono, Marco Scigliuzzo

Superconducting qubits are among the most advanced candidates for achieving fault-tolerant quantum computing. Despite recent significant advancements in the qubit lifetimes, the origin of the loss mechanism for state-of-the-art qubits is still subject to i ...

Nature Portfolio2024

Ultra-high quantum coherent and scalable superconducting circuit optomechanics, from topological lattices to quantum storage

Amir Youssefi

Mechanical oscillators can exhibit modes with ultra-low energy dissipation and compact form factors due to the slow velocity of acoustic waves, and are already used in applications ranging from timing to wireless filters. Over the past decade, novel ways i ...

EPFL2024

Electron-beam based nanoscale quantum controls

Hoda Shirzad

Advancing quantum technologies depends on the precise control of individual quantum systems, the so-called qubits, and the exploitation of their quantum properties. Nowadays, expanding the number of qubits to be entangled is at the core of the developments ...

EPFL2024

Emergence of highly coherent two-level systems in a noisy and dense quantum network

Sandrine Gerber, Gabriel Aeppli

Quantum sensors and qubits are usually two-level systems (TLS), the quantum analogues of classical bits assuming binary values 0 or 1. They are useful to the extent to which superpositions of 0 and 1 persist despite a noisy environment. The standard prescr ...

Nature Portfolio2024

Thouless pumping in Josephson junction arrays

Stavros Athanasiou

Recent advancements in fabrication techniques have enabled unprecedented clean interfaces and gate tunability in semiconductor-superconductor heterostructures. Inspired by these developments, we propose protocols to realize Thouless quantum pumping in elec ...

Scipost Foundation2024

Three-wave-mixing quantum-limited kinetic inductance parametric amplifier operating at 6 T near 1 K

Camille René Charles Roy, Simone Frasca, Guillaume Beaulieu, Pasquale Scarlino

Parametric amplifiers play a crucial role in modern quantum technology by enabling the enhancement of weak signals with minimal added noise. Traditionally, Josephson junctions have been the primary choice for constructing parametric amplifiers. Nevertheles ...

American Physical Society (APS)2024

Mitigation of frequency collisions in superconducting quantum processors

Marco Scigliuzzo

The reproducibility of qubit parameters is a challenge for scaling up superconducting quantum processors. Signal cross talk imposes constraints on the frequency separation between neighboring qubits. The frequency uncertainty of transmon qubits arising fro ...

Amer Physical Soc2023

Programmable frequency-bin quantum states in a nano-engineered silicon device

Matteo Galli, Marco Clementi

Frequency-bin qubits get the best of time-bin and dual-rail encodings, but require external modulators and pulse shapers to build arbitrary states. Here, instead, the authors work directly on-chip by controlling the interference of biphoton amplitudes gene ...

Nature Portfolio2023

Silicon spin qubits from laboratory to industry

Edoardo Charbon, Louis Hutin

Quantum computation (QC) is one of the most challenging quantum technologies that promise to revolutionize data computation in the long-term by outperforming the classical supercomputers in specific applications. Errors will hamper this quantum revolution ...

IOP Publishing Ltd2023

High-Kinetic Inductance Superconducting Technology for Quantum Applications

Simone Frasca

Superconducting materials present unique properties, which make a potential technological platform based on superconductors extremely appealing for a wide set of applications, both classical and not. Among these classes of materials, high-kinetic inductanc ...

EPFL2023

Quantum process tomography with unsupervised learning and tensor networks

Giuseppe Carleo

The impressive pace of advance of quantum technology calls for robust and scalable techniques for the characterization and validation of quantum hardware. Quantum process tomography, the reconstruction of an unknown quantum channel from measurement data, r ...

Nature Portfolio2023

Erbium and thulium on MgO(100)/Ag(100) as candidates for single atom qubits

Harald Brune, François Patthey, Stefano Rusponi, Marina Pivetta, Edgar Fernandes, Fabio Donati, Aparajita Singha

Lanthanide atoms on surfaces are an exceptional platform for atomic-scale magnetic information storage. However, their potential as qubits remains unexplored due to the limited number of experimental setups that can coherently drive the spins of single ada ...

AMER PHYSICAL SOC2023

Superconducting quantum interference at the atomic scale

Klaus Kern, Haonan Huang

A single spin in a Josephson junction can reverse the flow of the supercurrent by changing the sign of the superconducting phase difference across it. At mesoscopic length scales, these pi-junctions are employed in various applications, such as finding the ...

NATURE PORTFOLIO2022

Experimental QND measurements of complementarity on two-qubit states with IonQ and IBM Q quantum computers

Christophe Marcel Georges Galland, Nicolas Schwaller, Valeria Vento

We report the experimental nondemolition measurement of coherence, predictability and concurrence on a system of two qubits. The quantum circuits proposed by De Melo et al. (Phys Rev Lett 98(25):250501, 2007) are implemented on IBM Q (superconducting circu ...

SPRINGER2022

Controlling Atom-Photon Bound States in an Array of Josephson-Junction Resonators

Pasquale Scarlino, Marco Scigliuzzo

Engineering the electromagnetic environment of a quantum emitter gives rise to a plethora of exotic light -matter interactions. In particular, photonic lattices can seed long-lived atom-photon bound states inside photonic band gaps. Here, we report on the ...

American Physical Society2022

Anisotropic and nonlinear transport in microstructured 3D topological semimetals

Xiangwei Huang

Topological semimetals are frequently discussed as materials platforms for future electronics that exploit the remarkable properties of their quasiparticles. These ideas are mostly based on dispersion relations that mimic relativistic particles, such as We ...

EPFL2022

Variational dynamics as a ground-state problem on a quantum computer

Giuseppe Carleo, Filippo Vicentini, Stefano Barison

We propose a variational quantum algorithm to study the real-time dynamics of quantum systems as a ground -state problem. The method is based on the original proposal of Feynman and Kitaev to encode time into a register of auxiliary qubits. We prepare the ...

AMER PHYSICAL SOC2022

Extracting transport channel transmissions in scanning tunneling microscopy using superconducting excess current

Klaus Kern, Markus Etzkorn, Jacob Senkpiel

Transport through quantum coherent conductors, such as atomic junctions, is described by conduction channels. Information about the number of channels and their transmissions can be extracted from various sources, such as multiple Andreev reflections, dyna ...

AMER PHYSICAL SOC2022

A Cryo-CMOS Oscillator With an Automatic Common-Mode Resonance Calibration for Quantum Computing Applications

Edoardo Charbon, Fabio Sebastiano, Yue Chen

This article presents a 4-to-5 GHz LC oscillator operating at 4.2K for quantum computing applications. The phase noise (PN) specification of the oscillator is derived based on the control fidelity for a single-qubit operation. To reveal the substantial gap ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Energy Efficient Sensing using Steep Slope Devices

Teodor Rosca

Today, we are witnessing the Internet of Things (IoT) revolution, which facilitates and improves our lives in many aspects, but comes with several challenges related to the technology deployment at large scales. Handling ever growing amounts of information ...

EPFL2022