Single photons and quantum effects articles from across Nature Portfolio

A programmable integrated photonic circuit that works with single photons has enabled the construction of quantum-to-quantum Bernoulli factories, devices that process randomness in quantum states.

The Mpemba effect is an archetype for various anomalous relaxation phenomena. Here, the authors experimentally study a quantum version of the Mpemba effect in a single trapped ion system, where relaxation is exponentially accelerated by removing the excitation of the slowest decaying mode. This phenomenon, seen in Markovian open quantum systems containing Liouvillian exceptional points, indicates a link between the Mpemba effect and non-Hermitian physics.

Magnetoreception is used for navigation by migratory animals. Here the authors use spin dynamics simulations to show how asymmetric recombination of radical pairs enables sensitivity in cryptochromes for Earth-strength magnetic fields.

Non-equilibrium systems subject to periodic driving fields, known as Floquet materials, can host unique topological phases without static counterpart. This work targets the link between Floquet physics and cavity-QED systems, and unveils the emergence of quantum anomalous phases in the latter, pointing to the important entangled light-matter dynamics.

Coupling semiconductor spin qubits over long distances using a superconducting resonator makes different quantum architectures possible. Now, the coherent swapping of quantum states has been observed between qubits coupled using this design.

A programmable integrated photonic circuit that works with single photons has enabled the construction of quantum-to-quantum Bernoulli factories, devices that process randomness in quantum states.

In a device comprising two double quantum dots separated by a 250-μm-long superconducting resonator, virtual photons in the resonator are shown to mediate the coupling of electron spins between the quantum dots. When the spin–spin coupling is activated for a controlled duration, oscillations between the spins are observed.

Creating entangled photon pairs often requires intense excitation of nonlinear materials or the active manipulation of quantum devices. Now, entanglement between two photons has been created by scattering a laser off a passive quantum dot.

A quantum control technique is used to directly couple trapped-ion motional modes with high fidelity, enabling non-destructive measurements of the quantum harmonic oscillator states of atomic motion. The strong coupling rate and precise manipulation of the quantum states achieved with this technique could lead to advances in quantum information processing.

Acoustic resonators are a promising candidate for making quantum computers scalable. Coupled to a qubit, they have now produced squeezed mechanical states, demonstrating that they can implement a large variety of quantum algorithms.

The astronomy and quantum information science communities met together in a one-day workshop to share experiences and ideas on how to reach the next level — the quantum level — of astronomical interferometry.