124 citations · 692 across the 27 of their papers we have counts for
28 papers
Mitigating crosstalk errors for simultaneous single-qubit gates on a superconducting quantum processor
Jaap J. Wesdorp, Eric Hyyppä, Joona Andersson +61
Single-qubit gates on superconducting quantum processors are typically implemented using microwave pulses applied through dedicated control lines. However, these microwave pulses m…
A Superconducting Qubit-Resonator Quantum Processor with Effective All-to-All Connectivity
Michael Renger, Jeroen Verjauw, Nicola Wurz +62
In this work we introduce a superconducting quantum processor architecture that uses a transmission-line resonator to implement effective all-to-all connectivity between six transm…
Technology and Performance Benchmarks of IQM's 20-Qubit Quantum Computer
Leonid Abdurakhimov, Janos Adam, Hasnain Ahmad +111
Quantum computing has tremendous potential to overcome some of the fundamental limitations present in classical information processing. Yet, today's technological limitations in th…
Cryogenic microwave link for quantum local area networks
W. K. Yam, M. Renger, S. Gandorfer +16
Scalable quantum information processing with superconducting circuits is expected to advance from individual processors located in single dilution refrigerators to more powerful di…
Initial experimental results on a superconducting-qubit reset based on photon-assisted quasiparticle tunneling
V. A. Sevriuk, W. Liu, J. Rönkkö +15
We present here our recent results on qubit reset scheme based on a quantum-circuit refrigerator (QCR). In particular, we use the photon-assisted quasiparticle tunneling through a…
Long-distance transmon coupler with CZ gate fidelity above
Fabian Marxer, Antti Vepsäläinen, Shan W. Jolin +36
Tunable coupling of superconducting qubits has been widely studied due to its importance for isolated gate operations in scalable quantum processor architectures. Here, we demonstr…
Quantum behavior of a superconducting Duffing oscillator at the dissipative phase transition
Qi-Ming Chen, Michael Fischer, Yuki Nojiri +8
Understanding the non-deterministic behavior of deterministic nonlinear systems has been an implicit dream since Lorenz named it the "butterfly effect". A prominent example is the…
Recent Developments in Quantum-Circuit Refrigeration
Timm Fabian Mörstedt, Arto Viitanen, Vasilii Vadimov +7
We review the recent progress in direct active cooling of the quantum-electric degrees freedom in engineered circuits, or quantum-circuit refrigeration. In 2017, the invention of a…
The scattering coefficients of superconducting microwave resonators: II. System-bath approach
Qi-Ming Chen, Matti Partanen, Florian Fesquet +8
We describe a unified quantum approach for analyzing the scattering coefficients of superconducting microwave resonators with a variety of geometries. We also generalize the method…
Experimental quantum teleportation of propagating microwaves
K. G. Fedorov, M. Renger, S. Pogorzalek +9
The modern field of quantum communication thrives on promise to deliver efficient and unconditionally secure ways to exchange information by exploiting quantum laws of physics. Her…
Beyond the standard quantum limit of parametric amplification
M. Renger, S. Pogorzalek, Q. Chen +8
The low-noise amplification of weak microwave signals is crucial for countless protocols in quantum information processing. Quantum mechanics sets an ultimate lower limit of half a…
Bolometer operating at the threshold for circuit quantum electrodynamics
R. Kokkoniemi, J. -P. Girard, D. Hazra +7
Radiation sensors based on the heating effect of the absorbed radiation are typically relatively simple to operate and flexible in terms of the input frequency. Consequently, they…
Photon-number-dependent effective Lamb shift
Arto Viitanen, Matti Silveri, Máté Jenei +8
The Lamb shift, an energy shift arising from the presence of the electromagnetic vacuum, has been observed in various quantum systems and established as the part of the energy shif…
Broadband Tunable Phase Shifter For Microwaves
Jinli Zhang, Tianyi Li, Roope Kokkoniemi +8
We implement a broadly tunable phase shifter for microwaves based on superconducting quantum interference devices (SQUIDs) and study it both experimentally and theoretically. At di…
Quantum Fourier Transform in Oscillating Modes
Qi-Ming Chen, Frank Deppe, Re-Bing Wu +9
Quantum Fourier transform (QFT) is a key ingredient of many quantum algorithms where a considerable amount of ancilla qubits and gates are often needed to form a Hilbert space larg…
Fast control of dissipation in a superconducting resonator
Vasilii Sevriuk, Kuan Yen Tan, Eric Hyyppä +8
We report on fast tunability of an electromagnetic environment coupled to a superconducting coplanar waveguide resonator. Namely, we utilize a recently-developed quantum-circuit re…
Reconstruction Approach to Quantum Dynamics of Bosonic Systems
Akseli Mäkinen, Joni Ikonen, Matti Partanen +1
We propose an approach to analytically solve the quantum dynamics of bosonic systems. The method is based on reconstructing the quantum state of the system from the moments of its…
Calibration of cryogenic amplification chains using normal-metal--insulator--superconductor junctions
Eric Hyyppä, Máté Jenei, Shumpei Masuda +7
Various applications of quantum devices call for an accurate calibration of cryogenic amplification chains. To this end, we present a convenient calibration scheme and use it to ac…
Optimized heat transfer at exceptional points in quantum circuits
Matti Partanen, Jan Goetz, Kuan Yen Tan +12
Superconducting quantum circuits are potential candidates to realize a large-scale quantum computer. The envisioned large density of integrated components, however, requires a prop…
Qubit Measurement by Multichannel Driving
Joni Ikonen, Jan Goetz, Jesper Ilves +10
We theoretically propose and experimentally implement a method of measuring a qubit by driving it close to the frequency of a dispersively coupled bosonic mode. The separation of t…
Observation of a broadband Lamb shift in an engineered quantum system
Matti Silveri, Shumpei Masuda, Vasilii Sevriuk +9
The shift of energy levels owing to broadband electromagnetic vacuum fluctuations, the Lamb shift, has been pivotal in the development of quantum electrodynamics and in understandi…
Flux-tunable heat sink for quantum electric circuits
Matti Partanen, Kuan Yen Tan, Shumpei Masuda +10
Superconducting microwave circuits show great potential for practical quantum technological applications such as quantum information processing. However, fast and on-demand initial…
Cryogenic microwave source based on nanoscale tunnel junctions
Shumpei Masuda, Kuan Y. Tan, Matti Partanen +5
We experimentally realize an incoherent microwave source driven by voltage-controlled quantum tunneling of electrons through nanoscale normal-metal--insulator--superconductor junct…
Efficient protocol for qubit initialization with a tunable environment
Jani Tuorila, Matti Partanen, Tapio Ala-Nissila +1
We propose an efficient qubit initialization protocol based on a dissipative environment that can be dynamically adjusted. Here the qubit is coupled to a thermal bath through a tun…