A5051635219- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Quantum and electron transport phenomena
- Advanced Algebra and Geometry
- Black Holes and Theoretical Physics
- Quantum many-body systems
- Homotopy and Cohomology in Algebraic Topology
- Neural Networks and Reservoir Computing
- Physics of Superconductivity and Magnetism
- Spectroscopy and Quantum Chemical Studies
- Algebraic structures and combinatorial models
- Nonlinear Waves and Solitons
- Astrophysical Phenomena and Observations
- Quantum Mechanics and Applications
- Mechanical and Optical Resonators
- Photonic and Optical Devices
- Quantum optics and atomic interactions
- Advanced Topics in Algebra
- Superconducting and THz Device Technology
- Theoretical and Computational Physics
- Noncommutative and Quantum Gravity Theories
Kyung Hee University
2024-2025
D-Wave Systems (Canada)
2009-2020
Jet Propulsion Laboratory
2016
D-wave computers are designed to implement a single quantum algorithm called annealing. Are these really quantum? Researchers have found strong evidence that qubits in processor running the entangled mechanically.
A superconducting chip containing a regular array of flux qubits, tunable interqubit inductive couplers, an XY-addressable readout system, on-chip programmable magnetic memory, and sparse network analog control lines has been studied. The architecture the infrastructure used to it were designed facilitate implementation adiabatic quantum optimization algorithm. performance eight-qubit unit cell on this characterized by measuring its success in solving large set random Ising spin glass...
Understanding magnetic phases in quantum mechanical systems is one of the essential goals condensed matter physics, and advent prototype simulation hardware has provided new tools for experimentally probing such systems. We report on experimental realization a interacting Ising spins three-dimensional cubic lattices up to dimensions 8 × D-Wave processor (D-Wave Systems, Burnaby, Canada). The ability control read out state individual provides direct access several order parameters, which we...
A rf--superconducting quantum interference device (SQUID) flux qubit that is robust against fabrication variations in Josephson-junction critical currents and inductance has been implemented. Measurements of the persistent current tunneling energy between two lowest-lying states, both coherent incoherent regimes, are presented. These experimental results shown to be agreement with predictions a quantum-mechanical Hamiltonian whose parameters were independently calibrated, thus justifying...
We have designed, fabricated and operated a scalable system for applying independently programmable time-independent, limited time-dependent flux biases to control superconducting devices in an integrated circuit.Here we report on the operation of designed supply 64 circuit be unit cell adiabatic quantum optimization (AQO) system.The requires six digital address lines, two power handful global analog lines.
Quantum annealing (QA) is a heuristic algorithm for finding low-energy configurations of system, with applications in optimization, machine learning, and quantum simulation. Up to now, all implementations QA have been limited qubits coupled via single degree freedom. This gives rise stoquastic Hamiltonian that has no sign problem Monte Carlo (QMC) simulations. In this paper, we report implementation measurements two superconducting flux canonically conjugate degrees freedom (charge flux)...
An improved tunable coupling element for building networks of coupled rf-SQUID flux qubits has been experimentally demonstrated. This new form coupler, based upon the compound Josephson junction rf-SQUID, provides a sign and magnitude mutual inductance between with minimal nonlinear crosstalk from coupler tuning parameter into qubits. Quantitative agreement is shown an effective one-dimensional model coupler's potential measurements persistent current susceptibility.
A bstract We derive manifestly covariant actions of spinning particles starting from coadjoint orbits isometry groups, by using Hamiltonian reductions. show that the defining conditions a classical Lie group can be treated as constraints which generate another, dual , group. In case (inhomogeneous) orthogonal groups are (centrally-extended inhomogeneous) symplectic groups. This defines pair correspondence between and those group, whose quantum version is reductive à la Howe. explicitly how...
Worldline actions for various twistor particles in Anti de Sitter (AdS) spacetimes are constructed from the coadjoint orbits of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>S</a:mi><a:mi>p</a:mi><a:mo stretchy="false">(</a:mo><a:mn>4</a:mn><a:mo>,</a:mo><a:mi mathvariant="double-struck">R</a:mi><a:mo stretchy="false">)</a:mo></a:math>, <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mi>S</f:mi><f:mi>U</f:mi><f:mo...
We report measurements of macroscopic resonant tunneling between the two lowest energy states a pair magnetically coupled rf-SQUID flux qubits. This technique provides direct means observing two-qubit dynamics and probe environment to Measurements rate as function qubit bias show Gaussian line shape that is well matched theoretical predictions. Moreover, peak widths indicate each local whose fluctuations are uncorrelated with other qubit.
Superconducting microresonators have been successfully utilized as detection elements for a wide variety of applications. With multiplexing factors exceeding 1000 detectors per transmission line, they are the most scalable low-temperature detector technology demonstrated to date. For high-throughput applications, fewer can be coupled single wire but utilize larger per-detector bandwidth. all existing designs, fluctuations in fabrication tolerances result non-uniform shift resonance frequency...
Worldline actions for various twistor particles in AdS spacetimes are constructed from the coadjoint orbits of $Sp(4,\mathbb R)$, $SU(2,2)$ and $O^*(8)$ as constrained Hamiltonian systems. The constraints associated with dual groups, respectively identified $O(p,M-p)$, $U(p, M-p)$ $Sp(p, M-p)$. These presented a universal form by making use variables taking value $\mathbb R$, C$ H$, respectively. We find that massless, massive conformal (namely singletons) any spins appear compact groups...
Quantum computers must achieve large-scale, fault-tolerant operation to deliver on their promise of transformational processing power [1-4]. This will require thousands or millions high-fidelity quantum gates and similar numbers qubits [5]. Demonstrations using neutral-atom trapped manipulated by lasers have shown that this modality can provide high two-qubit gate (CZ) fidelities scalable [6-10]. However, the in these demonstrations are driven do not resolve individual qubits, with universal...
We derive manifestly covariant actions of spinning particles starting from coadjoint orbits isometry groups, by using Hamiltonian reductions. show that the defining conditions a classical Lie group can be treated as constraints which generate another, dual, group. In case (inhomogeneous) orthogonal dual groups are (centrally-extended inhomogeneous) symplectic groups. This defines pair correspondence between and those group, whose quantum version is reductive à la Howe. explicitly how various...
We study the construction of a manifestly covariant worldline action from coadjoint orbit. A orbit is submanifold in dual vector space Lie algebra and generated by actions. Since symplectic space, we derive particle two-form. One subtlety formulating actions orbits choosing coordinate system that sufficiently illustrates physical properties particles. introduce Hamiltonian constraints defining conditions isometry. This allows us to write action. demonstrate our method both massive massless...