A5018111279- Quantum Computing Algorithms and Architecture
- Quantum and electron transport phenomena
- Quantum Information and Cryptography
- Advancements in Semiconductor Devices and Circuit Design
- Quantum-Dot Cellular Automata
- Quantum many-body systems
- Physics of Superconductivity and Magnetism
- Spectroscopy Techniques in Biomedical and Chemical Research
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum optics and atomic interactions
- Spectroscopy and Chemometric Analyses
- Spectroscopy and Quantum Chemical Studies
Google (United States)
2017-2021
As the search continues for useful applications of noisy intermediate scale quantum devices, variational simulations fermionic systems remain one most promising directions. Here, we perform a series chemistry largest which involved dozen qubits, 78 two-qubit gates, and 114 one-qubit gates. We model binding energy ${\rm H}_6$, H}_8$, H}_{10}$ H}_{12}$ chains as well isomerization diazene. also demonstrate error-mitigation strategies based on $N$-representability dramatically improve effective...
A key step toward demonstrating a quantum system that can address difficult problems in physics and chemistry will be performing computation beyond the capabilities of any classical computer, thus achieving so-called supremacy. In this study, we used nine superconducting qubits to demonstrate promising path By individually tuning qubit parameters, were able generate thousands distinct Hamiltonian evolutions probe output probabilities. The measured probabilities obey universal distribution,...
Superconducting qubits are an attractive platform for quantum computing since they have demonstrated high-fidelity gates and extensibility to modest system sizes. Nonetheless, outstanding challenge is stabilizing their energy-relaxation times, which can fluctuate unpredictably in frequency time. Here, we use as spectral temporal probes of individual two-level-system defects provide direct evidence that responsible the largest fluctuations. This research lays foundation qubit performance...
Quantum algorithms offer a dramatic speedup for computational problems in material science and chemistry. However, any near-term realizations of these will need to be optimized fit within the finite resources offered by existing noisy hardware. Here, taking advantage adjustable coupling gmon qubits, we demonstrate continuous two-qubit gate set that can provide threefold reduction circuit depth as compared standard decomposition. We implement two families: an imaginary swap-like (iSWAP-like)...
We present a fabrication process for fully superconducting interconnects compatible with qubit technology. These allow the three dimensional integration of quantum circuits without introducing lossy amorphous dielectrics. They are composed indium bumps several microns tall separated from an aluminum base layer by titanium nitride which serves as diffusion barrier. measure whole structure to be (transition temperature 1.1 K), limited aluminum. have average critical current 26.8 mA, and...
By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides its two-sided environmental noise spectral density over range frequencies around 2k_{B}T/h≈1 GHz, allowing for observation classical-quantum crossover. Below crossover point, symmetric component follows 1/f power law that matches magnitude near 1 Hz. The antisymmetric displays 1/T dependence below 100 mK, providing dynamical evidence paramagnetic environment. Extrapolating spectrum predicts linewidth and...
While quantum processors are typically cooled to <; 25 mK avoid thermal disturbances their delicate states, all qubits still suffer decoherence and gate errors. As such, error correction is needed fully harness the power of computing (QC). Current projections indicate that > 1,000 physical will be required encode one error-corrected qubit [1]. Implementing a system with likely require moving from contemporary paradigm where control readout processor carried out using racks room temperature...
Josephson junctions form the essential non-linearity for almost all superconducting qubits. The junction is formed when two electrodes come within $\sim$1 nm of each other. Although capacitance these a small fraction total qubit capacitance, nearby electric fields are more concentrated in dielectric surfaces and can contribute substantially to dissipation. We have developed technique experimentally investigate effect on quality devices. use $\lambda$/4 coplanar waveguide resonators emulate...
We demonstrate diabatic two-qubit gates with Pauli error rates down to $4.3(2)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ in as fast 18 ns using frequency-tunable superconducting qubits. This is achieved by synchronizing the entangling parameters minima leakage channel. The synchronization shows a landscape gate parameter space that agrees model predictions and facilitates robust tune-up. test both iswap-like cphase cross-entropy benchmarking. presented approach can be extended...
Strongly correlated quantum systems give rise to many exotic physical phenomena, including high-temperature superconductivity. Simulating these on computers may avoid the prohibitively high computational cost incurred in classical approaches. However, systematic errors and decoherence effects presented current devices make it difficult achieve this. Here, we simulate dynamics of one-dimensional Fermi-Hubbard model using 16 qubits a digital superconducting processor. We observe separations...
We develop a high speed on-chip flux measurement using capacitively shunted SQUID as an embedded cryogenic transducer and apply this technique to the qualification of near-term scalable printed circuit board (PCB) package for frequency tunable superconducting qubits. The is LC resonator where applied changes resonant frequency. microwave tone probe use time-domain homodyne extract reflected phase function SQUID. response bandwidth 2.6 GHz with maximum gain $\rm 1200^\circ/\Phi_0$ allowing us...
Two-level-system (TLS) defects in amorphous dielectrics are a major source of noise and decoherence solid-state qubits. Gate-dependent non-Markovian errors caused by TLS-qubit coupling detrimental to fault-tolerant quantum computation have not been rigorously treated the existing literature. In this work, we derive dynamics between TLS qubits during SWAP-like two-qubit gate associated average fidelity for frequency-tunable Transmon This dependent error model facilitates using as sensors...