Publications associées à Charge qubit

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

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

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

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

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

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

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

Probing structural and dynamic properties of MAPbCl3 hybrid perovskite using Mn2+ EPR

Michael Allan Hope, Yuxuan Zhang

Hybrid methylammonium (MA) lead halide perovskites have emerged as materials exhibiting excellent photovoltaic performance related to their rich structural and dynamic properties. Here, we use multifrequency (X-, Q-, and W-band) electron paramagnetic reson ...

Royal Soc Chemistry2024

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

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

A squeezed mechanical oscillator with millisecond quantum decoherence

Tobias Kippenberg, Amir Youssefi, Mahdi Chegnizadeh, Shingo Kono

An enduring challenge in constructing mechanical-oscillator-based hybrid quantum systems is to ensure engineered coupling to an auxiliary degree of freedom and maintain good mechanical isolation from the environment, that is, low quantum decoherence, consi ...

NATURE PORTFOLIO2023

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

Christophe Marcel Georges Galland, Valeria Vento, Nicolas Schwaller

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

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

Cryogenic CMOS Integrated Circuits for Scalable Readout of Silicon Quantum Computers

Andrea Ruffino

Quantum computing promises to revolutionize our lives, achieving unprecedented computational powers and unlocking new possibilities in drug discovery, chemical simulations and cryptography. The fundamental unit of computation of a quantum computer is the q ...

EPFL2021

Cryogenic CMOS Circuits and Systems: Challenges and Opportunities in Designing the Electronic Interface for Quantum Processors

Edoardo Charbon, Fabio Sebastiano

Quantum computing could potentially offer faster solutions for some of today's classically intractable problems using quantum processors as computational support for quantum algorithms [1]. Quantum processors, in the most frequent embodiment, comprise an a ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

Universal Quantum Computing Using Electronuclear Wavefunctions of Rare-Earth Ions

Gabriel Aeppli

We propose a scheme for universal quantum computing based on Kramers rare-earth ions. Their nuclear spins in the presence of a Zeeman-split electronic crystal field ground state act as "passive" qubits that store quantum information. The "active" qubits ar ...

AMER PHYSICAL SOC2021

Microwave-to-Optical Transduction with Gallium Phosphide Electro-Optomechanical Devices

Simon Benjamin Klaus Hönl

Quantum computing is one of the great scientific challenges of the 21st century. Small-scale systems today promise to surpass classical computers in the coming years and to enable the solution of classically intractable computational tasks in the fields of ...

EPFL2021

A Fully-Integrated 40-nm 5-6.5 GHz Cryo-CMOS System-on-Chip with I/Q Receiver and Frequency Synthesizer for Scalable Multiplexed Readout of Quantum Dots

Edoardo Charbon, Andrea Ruffino, Yatao Peng

Quantum computing holds the promise to solve many of today's intractable problems. A solid-state quantum computer (QC) is generally made of an array of qubits implemented in one of many solid-state technologies and operating at deep-cryogenic temperatures ...

IEEE2021

Local excitations in amorphous solids

Wencheng Ji

Amorphous solids are structurally disordered. They are very common and include glasses, colloids, and granular materials, but are far less understood than crystalline solids. Key aspects of these materials are controlled by the presence of excitations in w ...

EPFL2021

Variational approach to time-dependent fluorescence of a driven qubit

Yang Zhao

We employ the Dirac-Frenkel variational principle and the multiple Davydov ansatz to study time-dependent fluorescence spectra of a driven qubit in the weak to strong qubit-reservoir coupling regimes, where both the Rabi frequency and the spontaneous decay ...

AMER PHYSICAL SOC2020

A Review on Quantum Computing: From Qubits to Front-end Electronics and Cryogenic MOSFET Physics

Jean-Michel Sallese, Farzan Jazaeri, Seyed Armin Tajalli, Arnout Lodewijk M Beckers

Quantum computing (QC) has already entered the industrial landscape and several multinational corporations have initiated their own research efforts. So far, many of these efforts have been focusing on superconducting qubits, whose industrial progress is c ...

IEEE2019