277 citations · 1k across the 27 of their papers we have counts for
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Performance optimization of cascaded traveling wave Josephson parametric amplifiers
Ilari Lilja, Ekaterina Mukhanova, Stanislav Khaldeev +3
Traveling-wave parametric amplifiers (TWPAs) based on Josephson metamaterials provide broadband gain with near-quantum-limited added noise. Whereas long nonlinear metamaterial devi…
Phase-sensitive cascade quantum amplifier with nearly noiseless operation
Ilari Lilja, Ekaterina Mukhanova, Michael Perelshtein +5
Phase-sensitive parametric devices enable quadrature-selective amplification with the potential for sub-quantum-limited noise performance. In this work, we investigate the operatio…
Native-oxide-passivated trilayer junctions for superconducting qubits
Pankaj Sethi, Om Prakash, Jukka-Pekka Kaikkonen +15
Superconducting qubits in today's quantum processing units are typically fabricated with angle-evaporated aluminum--aluminum-oxide--aluminum Josephson junctions. However, there is…
Methods to achieve near-millisecond energy relaxation and dephasing times for a superconducting transmon qubit
Mikko Tuokkola, Yoshiki Sunada, Heidi Kivijärvi +6
Superconducting qubits are one of the most promising physical systems for implementing quantum computers. However, executing quantum algorithms of practical computational advantage…
Correlation measurement of propagating microwave photons at millikelvin
Aarne Keränen, Qi-Ming Chen, András Gunyhó +5
Microwave photons are important carriers of quantum information in many promising platforms for quantum computing. They can be routinely generated, controlled, and teleported in ex…
Near-ground state cooling in electromechanics using measurement-based feedback and Josephson parametric amplifier
Ewa Rej, Richa Cutting, Debopam Datta +5
Feedback-based control of nano- and micromechanical resonators can enable the study of macroscopic quantum phenomena and also sensitive force measurements. Here, we demonstrate the…
Single-Shot Readout of a Superconducting Qubit Using a Thermal Detector
András M. Gunyhó, Suman Kundu, Jian Ma +8
Measuring the state of qubits is one of the fundamental operations of a quantum computer. Currently, state-of-the-art high-fidelity single-shot readout of superconducting qubits re…
Generation and structuring of multipartite entanglement in Josephson parametric system
K. V. Petrovnin, M. R. Perelshtein, T. Korkalainen +4
Quantum correlations are a vital resource in advanced information processing based on quantum phenomena. Remarkably, the vacuum state of a quantum field may act as a key element fo…
Qubit-compatible substrates with superconducting through-silicon vias
K. Grigoras, N. Yurttagül, J. -P. Kaikkonen +21
We fabricate and characterize superconducting through-silicon vias and electrodes suitable for superconducting quantum processors. We measure internal quality factors of a million…
Broadband continuous variable entanglement generation using Kerr-free Josephson metamaterial
Michael Perelshtein, Kirill Petrovnin, Visa Vesterinen +13
Entangled microwave photons form a fundamental resource for quantum information processing and sensing with continuous variables. We use a low-loss Josephson metamaterial comprisin…
A low-noise on-chip coherent microwave source
Chengyu Yan, Juha Hassel, Visa Vesterinen +5
The scaleup of quantum computers operating in the microwave domain requires advanced control electronics, and the use of integrated components that operate at the temperature of th…
Characterizing cryogenic amplifiers with a matched temperature-variable noise source
Slawomir Simbierowicz, Visa Vesterinen, Joshua Milem +7
We present a cryogenic microwave noise source with a characteristic impedance of 50 , which can be installed in a coaxial line of a cryostat. The bath temperature of the noise s…
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…
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…
Detecting bit-flip errors in a logical qubit using stabilizer measurements
D. Ristè, S. Poletto, M. -Z. Huang +4
Quantum data is susceptible to decoherence induced by the environment and to errors in the hardware processing it. A future fault-tolerant quantum computer will use quantum error c…