We introduce a multi-step protocol for optical quantum state engineering that
performs as deterministic "bright quantum scissors" (BQS), namely truncates an
arbitrary input quantum state to have at least a certain number of photons. The
protocol exploits single-photon pulses and is based on the effect of
single-photon Raman interaction, which is implemented with a single three-level
$\Lambda$ system (e.g. a single atom) Purcell-enhanced by a single-sided
cavity. A single step of the protocol realises the inverse of the bosonic

The equivalence principle in combination with the special relativistic
equivalence between mass and energy, $E=mc^2$, is one of the cornerstones of
general relativity. However, for composite systems a long-standing result in
general relativity asserts that the passive gravitational mass is not simply
equal to the total energy. This seeming anomaly is supported by all explicit
derivations of the dynamics of bound systems, and is only avoided after
time-averaging. Here we rectify this misconception and derive from first

This paper is devoted to the study of the evolution of holographic complexity
after a local perturbation of the system at finite temperature. We calculate
the complexity using both the complexity=action(CA) and the
complexity=volume(CA) conjectures and find that the CV complexity of the total
state shows the unbounded late time linear growth. The CA computation shows
linear growth with fast saturation to a constant value. We estimate the CV and
CA complexity linear growth coefficients and show, that finite temperature

We may infer a transition $|n \rangle \to |m \rangle$ between energy
eigenstates of an open quantum system by observing the emission of a photon of
Bohr frequency $\omega_{mn} = (E_n-E_m) / \hbar$. In addition to the
"collapses" to the state $|m\rangle$, the measurement must also have brought
into existence the pre-measurement state $|n \rangle$. As quantum trajectories
are based on past observations, the condition state will jump to $| m \rangle$,
but the state $|n\rangle$ does not feature in any essential way. We resolve

We introduce an approach to find the Tomita-Takesaki modular flow for
multi-component regions in chiral conformal field theory. Our method is based
only locality (or braid-relations) of primary fields and the so-called
Kubo-Martin-Schwinger (KMS) condition. These methods can be used to transform
the problem to a Riemann-Hilbert problem on a covering of the complex plane cut
along the regions. The method for instance gives a formula for the modular flow
in the case of a thermal state for the free fermion net, but is in principle

Recent technological breakthroughs have precipitated the availability of
specialized devices that promise to solve NP-Hard problems faster than standard
computers. These `Ising Machines' are however analog in nature and as such
inevitably have implementation errors. We find that their success probability
decays exponentially with problem size for a fixed error level, and we derive a
sufficient scaling law for the error in order to maintain a fixed success
probability. We corroborate our results with experiment and numerical

We propose a novel type of composite light-matter interferometer based on a
supersolid-like phase of a driven Bose-Einstein condensate coupled to a pair of
degenerate counterpropagating electromagnetic modes of an optical ring cavity.
The supersolid-like condensate under the influence of the gravity drags the
cavity optical potential with itself, thereby changing the relative phase of
the two {cavity electromagnetic fields}. Monitoring the phase evolution of the

Geometric integrators of the Schr\"{o}dinger equation conserve exactly many
invariants of the exact solution. Among these integrators, the split-operator
algorithm is explicit and easy to implement, but, unfortunately, is restricted
to systems whose Hamiltonian is separable into a kinetic and potential terms.
Here, we describe several implicit geometric integrators applicable to both
separable and non-separable Hamiltonians, and, in particular, to the
nonadiabatic molecular Hamiltonian in the adiabatic representation. These

In compressed sensing one uses known structures of otherwise unknown signals
to recover them from as few linear observations as possible. The structure
comes in form of some compressibility including different notions of sparsity
and low rankness. In many cases convex relaxations allow to efficiently solve
the inverse problems using standard convex solvers at almost-optimal sampling
rates. A standard practice to account for multiple simultaneous structures in

Nuclear spins in the solid state have long been envisaged as a platform for
quantum computing, due to their long coherence times and excellent
controllability. Measurements can be performed via localised electrons, for
example those in single atom dopants or crystal defects. However, establishing
long-range interactions between multiple dopants or defects is challenging.
Conversely, in lithographically-defined quantum dots, tuneable interdot
electron tunnelling allows direct coupling of electron spin-based qubits in