Single shot error correction is a technique for correcting physical errors
using only a single round of noisy measurements, such that any residual noise
affects a small number of qubits. Not all error correcting codes support
single-shot error correction and until recently all known cases have been
topological codes in 3 or more dimensions. We establish a general theory of
single-shot error correction that is not limited to topological codes. A
crucial property is found to be code soundness from the literature on locally

We present a new scheme for teleporting a quantum state between two parties
whose local reference frames are misaligned by the action of a finite symmetry
group. Unlike other proposals, our scheme requires the same amount of classical
communication and entangled resources as conventional teleportation, does not
reveal any reference frame information, and is robust against changes in
reference frame alignment while the protocol is underway. The mathematical

Quantum microwave photonics aims at generating, routing, and manipulating
propagating quantum microwave fields in the spirit of optical photonics. To
this end, the strong nonlinearities of superconducting quantum circuits can be
used to either improve or move beyond the implementation of concepts from the
optical domain. In this context, the design of a well-controlled broadband
environment for the superconducting quantum circuits is a central task. In this
work, we place a superconducting transmon qubit in one arm of an on-chip

In this letter, we investigate the quantum optical properties of
driven-dissipative nonlinear systems in a cascade configuration. We show that
pumping a nonlinear system with a state having a noncoherent statistics, can
improve the antibunching of the output state and, consequently, the
nonclassicality of the whole system. Furthermore, we show that is possible to
generate entanglement through dissipative coupling. These results applies to a
broad category of physical systems with a Kerr-like non-linearity, from Rydberg

In this work we introduce the randomness which is truly quantum mechanical in
nature arising as an act of measurement. For a composite classical system we
have the joint entropy to quantify the randomness present in the total system
and that happens to be equal to the sum of the entropy of one subsystem and the
conditional entropy of the other subsystem given we know the first system. The
same analogy caries over to the quantum setting by replacing the Shannon

We argue that space and space-time emerge as a consequence of dynamical
collapse of the wave function of macroscopic objects. Locality and separability
are properties of our approximate, emergent universe. At the fundamental level,
space-time is non-commutative, and dynamics is non-local and non-separable.

We investigate the finite-size Dicke model with photon leakage. It is shown
that the symmetry breaking states, which are characterized by non-vanishing
$\langle \hat{a} \rangle \neq 0$ and correspond to the ground states in the
superradiant phase in the thermodynamic limit, are stable, while the
eigenstates of the isolated finite-size Dicke Hamiltonian conserve parity
symmetry. We introduce and analyze an effective master equation that describes
the dynamics of a pair of the symmetry breaking states that are the degenerate

We find a simple model of an insulating state of a quantum wire which has a
single isolated edge mode. We argue that, when brought to proximity, the edge
modes on independent wires naturally form Bell entangled states which could be
used for elementary quantum processes such as teleportation. We give an example
of an algorithm which teleports the spin state of an electron from one quantum
wire to another.

Recent computations involving quantum processing units (QPUs) have
demonstrated a series of challenges inherent to hybrid classical-quantum
programming, compilation, execution, and verification and validation. Despite
considerable progress, system-level noise, limited low-level instructions sets,
remote access models, and an overall lack of portability and classical
integration presents near-term programming challenges that must be overcome in
order to enable reliable scientific quantum computing and support robust

We experimentally demonstrate a real-time optical quantum random number
generator by measuring vacuum fluctuation. Analysis towards the impact of
practical system components is done to obtain higher min-entropy, in which
min-entropy represents extractable quantum randomness. The corresponding
min-entropy is calculated as 6.93 bits per sample in our experiment when system
components' parameters are suitably adjusted. To bridge the speed gap between
the fast randomness generation and the slow randomness extraction, we propose