80 citations · 508 across the 22 of their papers we have counts for
23 papers
Coherent and ultra-low-power EDSR with a flopping-mode spin qubit in germanium
Alexei Orekhov, Wonjin Jang, Pan Zhang +13
Hole spin qubits in semiconductor quantum dots (QDs) enable high-fidelity all-electric control, but conventional electric dipole spin resonance (EDSR) can require substantial rf dr…
Engineering two-qubit gates via anisotropic exchange in germanium spin qubits
Leonardo Massai, Bence Hetényi, Eoin G. Kelly +14
Germanium hole spin qubits are a promising and versatile platform for quantum computation and simulation. In this system, strong spin-orbit interaction (SOI) renders the single-qub…
Disentangling orbital and confinement contributions to -factor in Ge/SiGe hole quantum dots
L. Sommer, I. Seidler, F. J. Schupp +12
Spin qubits are typically operated in the lowest orbital of a quantum dot to minimize interference from nearby states. In valence-band hole systems, strong spin-orbit coupling link…
Spatial uniformity of g-tensor and spin-orbit interaction in germanium hole spin qubits
Inga Seidler, Bence Hetényi, Lisa Sommer +12
Holes in Ge/SiGe heterostructures are now a leading platform for semiconductor spin qubits, thanks to the high confinement quality, two-dimensional arrays, high tunability, and lar…
Resonant two-qubit gates for fermionic simulations with spin qubits
Konstantinos Tsoukalas, Alexei Orekhov, Bence Hetényi +15
In gate-defined semiconductor spin qubits, the highly tunable Heisenberg exchange interaction is leveraged to implement fermionic two-qubit gates such as CZ and SWAP. However, the…
Identifying and mitigating errors in hole spin qubit readout
Eoin Gerard Kelly, Leonardo Massai, Bence Hetényi +14
High-fidelity readout of spin qubits in semiconductor quantum dots can be achieved by combining a radio-frequency (RF) charge sensor together with spin-to-charge conversion and Pau…
A dressed singlet-triplet qubit in germanium
Konstantinos Tsoukalas, Uwe von Lüpke, Alexei Orekhov +15
In semiconductor hole spin qubits, low magnetic field () operation extends the coherence time () but proportionally reduces the gate speed. In contrast, singlet-…
Direct microwave spectroscopy of Andreev bound states in planar Ge Josephson junctions
M. Hinderling, S. C. ten Kate, M. Coraiola +7
We demonstrate microwave measurements of the Andreev bound state (ABS) spectrum in planar Josephson junctions (JJs) defined in Ge high mobility two-dimensional hole gases contacted…
Impact of interface traps on charge noise, mobility and percolation density in Ge/SiGe heterostructures
L. Massai, B. Hetényi, M. Mergenthaler +8
Hole spins in Ge/SiGe heterostructure quantum dots have emerged as promising qubits for quantum computation. The strong spin-orbit coupling (SOC), characteristic of heavy-hole stat…
Capacitive crosstalk in gate-based dispersive sensing of spin qubits
Eoin G. Kelly, Alexei Orekhov, Nico Hendrickx +8
In gate-based dispersive sensing, the response of a resonator attached to a quantum dot gate is detected by a reflected radio-frequency signal. This enables fast readout of spin qu…
Sweet-spot operation of a germanium hole spin qubit with highly anisotropic noise sensitivity
N. W. Hendrickx, L. Massai, M. Mergenthaler +5
Spin qubits defined by valence band hole states comprise an attractive candidate for quantum information processing due to their inherent coupling to electric fields enabling fast…
A compact and versatile cryogenic probe station for quantum device testing
Mathieu de Kruijf, Simon Geyer, Toni Berger +4
Fast feedback from cryogenic electrical characterization measurements is key for the development of scalable quantum computing technology. At room temperature, high-throughput devi…
Radio-frequency characterization of a supercurrent transistor made from a carbon nanotube
M. Mergenthaler, F. J. Schupp, A. Nersisyan +6
A supercurrent transistor is a superconductor-semiconductor hybrid device in which the Josephson supercurrent is switched on and off using a gate voltage. While such devices have b…
Effects of surface treatments on flux tunable transmon qubits
M. Mergenthaler, C. Müller, M. Ganzhorn +9
One of the main limitations in state-of-the art solid-state quantum processors are qubit decoherence and relaxation due to noise in their local environment. For the field to advanc…
Ultrahigh Vacuum Packaging and Surface Cleaning for Quantum Devices
M. Mergenthaler, S. Paredes, P. Müller +7
We describe design, implementation and performance of an ultra-high vacuum (UHV) package for superconducting qubit chips or other surface sensitive quantum devices. The UHV loading…
Benchmarking the noise sensitivity of different parametric two-qubit gates in a single superconducting quantum computing platform
M. Ganzhorn, G. Salis, D. J. Egger +8
The possibility to utilize different types of two-qubit gates on a single quantum computing platform adds flexibility in the decomposition of quantum algorithms. A larger hardware-…
Calibration of the cross-resonance two-qubit gate between directly-coupled transmons
A. D. Patterson, J. Rahamim, T. Tsunoda +8
Quantum computation requires the precise control of the evolution of a quantum system, typically through application of discrete quantum logic gates on a set of qubits. Here, we us…
Realization of a Carbon-Nanotube-Based Superconducting Qubit
Matthias Mergenthaler, Ani Nersisyan, Andrew Patterson +6
Hybrid circuit quantum electrodynamics (QED) involves the study of coherent quantum physics in solid state systems via their interactions with superconducting microwave circuits. H…
Radio-frequency optomechanical characterization of a silicon nitride drum
A. N. Pearson, K. E. Khosla, M. Mergenthaler +3
On-chip actuation and readout of mechanical motion is key to characterize mechanical resonators and exploit them for new applications. We capacitively couple a silicon nitride memb…
Strong coupling of microwave photons to antiferromagnetic fluctuations in an organic magnet
M. Mergenthaler, J. Liu, J. J. Le Roy +10
Coupling between a crystal of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radicals and a superconducting microwave resonator is investigated in a circuit quantum electrodynamics…
Observing Coherence Effects in an Overdamped Quantum System
Y. -H. Lien, G. Barontini, M. Scheucher +3
It is usually considered that the spectrum of an optical cavity coupled to an atomic medium does not exhibit a normal-mode splitting unless the system satisfies the strong coupling…
Hyperfine and spin-orbit coupling effects on decay of spin-valley states in a carbon nanotube
T. Pei, A. Pályi, M. Mergenthaler +5
The decay of spin-valley states is studied in a suspended carbon nanotube double quantum dot via leakage current in Pauli blockade and via dephasing and decoherence of a qubit. Fro…
Resonant optomechanics with a vibrating carbon nanotube and a radio-frequency cavity
Natalia Ares, Tian Pei, Aquila Mavalankar +4
In an optomechanical setup, the coupling between cavity and resonator can be increased by tuning them to the same frequency. We study this interaction between a carbon nanotube res…