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We provide an algorithm that uses Bayesian randomized benchmarking in concert
with a local optimizer, such as SPSA, to find a set of controls that optimizes
that average gate fidelity. We call this method Bayesian ACRONYM tuning as a
reference to the analogous ACRONYM tuning algorithm. Bayesian ACRONYM
distinguishes itself in its ability to retain prior information from
experiments that use nearby control parameters; whereas traditional ACRONYM
tuning does not use such information and can require many more measurements as

We report on cryogenic coupling of organic molecules to ring microresonators
obtained by looping sub-wavelength waveguides (nanoguides). We discuss
fabrication and characterization of the chip-based nanophotonic elements which
yield resonator finesse in the order of 20 when covered by molecular crystals.
Our observed extinction dips from single molecules reach 22%, consistent with
the expected Purcell enhancements up to 11 folds. Future efforts will aim at

Recent experimental work with silicon qubits has shown that it is possible,
using an inhomogeneous magnetic field, to strongly couple modes of a microwave
resonator to the spin of a single electron trapped in a double quantum dot.
This suggests the possibility of realizing long-range spin-spin interactions
mediated by cavity photons. We present our theoretical calculation of effective
interactions between distant quantum dot spins coupled by a resonator, and

Nonlocality and contextuality are at the root of conceptual puzzles in
quantum mechanics, and are key resources for quantum advantage in
information-processing tasks. Bell nonlocality is best understood as the
incompatibility between quantum correlations and the classical theory of
causality, applied to relativistic causal structure. Contextuality, on the
other hand, is on a more controversial foundation. In this work, I provide a
common conceptual ground between nonlocality and contextuality as violations of

The system of a proton and an electron in an inert and impenetrable spherical
cavity is studied by solving Schr\"{o}dinger equation with the correct boundary
conditions. The differential equation of a hydrogen atom in a cavity is
derived. The numerical results are obtained with the help a power and efficient
few-body method, Gaussian Expansion Method. The results show that the correct
implantation of the boundary condition is crucial for the energy spectrum of
hydrogen in a small cavity.

We propose a theoretical method to enhance the coherent dipole coupling
between two atoms in an optical cavity via parametrically squeezing the cavity
mode. In the present scheme, conditions for coherent coupling are derived in
detail and diverse dynamics of the system can be obtained by regulating system
parameters. In the presence of environmental noise, an auxiliary squeezed field
is employed to suppress, and even completely eliminate the additional noise

Anticrossing behavior between magnons in a non-collinear chiral magnet
Cu$_2$OSeO$_3$ and a two-mode X-band microwave resonator was studied in the
temperature range 5-100K. In the field-induced ferrimagnetic phase, we observed
a strong coupling regime between magnons and two microwave cavity modes with a
cooperativity reaching 3600. In the conical phase, cavity modes are
dispersively coupled to a fundamental helimagnon mode, and we demonstrate that
the magnetic phase diagram of Cu$_2$OSeO$_3$ can be reconstructed from the

Everett's Relative State Interpretation (aka Many Worlds Interpretation) has
gained increasing interest due to the progress understanding the role of
decoherence. In order to fulfill its promise as a realistic description of the
physical world, two postulates are formulated. In short they are 1) for a
system with continuous coordinates $\mathbf x$, discrete variable $j$, and
state $\psi_j(\mathbf x)$, the density $\rho_j(\mathbf x)=|\psi_j(\mathbf
x)|^2$ gives the distribution of the location of the system with the respect to

Atoms in spatially dependent light fields are attracted to local intensity
maxima or minima depending on the sign of the frequency difference between the
light and the atomic resonance. For light fields confined in open high-Q
optical resonators the backaction of the atoms onto the light field generates
dissipative dynamic opto-mechanical potentials, which can be used to cool and
trap the atoms. Extending the conventional case of high field seekers to the

We revisit the calculation of multi-interval modular Hamiltonians for free
fermions using a Euclidean path integral approach. We show how the
multi-interval modular flow is obtained by gluing together the single interval
modular flows. Using this relation, we obtain an exact expression for the
multi-interval modular Hamiltonian and entanglement entropy in agreement with
existing results. An essential ingredient in our derivation is the introduction
of the \emp{modular action}. This determines the non-local field theory