Graph states are one of the most significant classes of entangled states, serving as the quantum resources for quantum technologies. Recently, integrated quantum photonics is becoming a promising platform for quantum information processing, enabling the generation, manipulation, and measurement of photonic quantum states. This article summarizes state-of-the-art experimental progress and advances in the chip-based photonic graph states.

Squeezed vacuum state of light is an important concept of quantum optics which has an uncertainty reduction in a specific quadrature compared to the coherent vacuum state. The coherent Ising machines (CIMs) based on the squeezed state are capable of searching the ground state of the Ising model, which can be used to solve combinatorial optimization problems and have been experimentally demonstrated to have excellent computational performance. This review introduces the recent progress of a CIM hardware solver based on optical parametric oscillators, including the delayed optical path scheme and a measurement feedback scheme. Also, the basic principles, unique advantages, and potential challenges are described. We expect that the applications of large-scale CIM hardware solvers will have a huge impact on the acceleration of the computation power.

Boron neutron capture therapy (BNCT) has been attracting interest as a new radiation modality for cancer therapy because it can selectively destroy cancer cells while maintaining the healthy state of surrounding normal cells. Many experimental trials have demonstrated significant BNCT treatment efficacy using neutron beams from research reactors. However, nuclear reactor technology cannot be scaled to sites in hospitals delivering patient treatment. Therefore, compact accelerator-based neutron sources that could be installed in many hospitals are under development or have even been commissioned at many facilities around the world. In Korea, a radio-frequency (RF) linac-based BNCT (A-BNCT) facility is under development by DawonMedax (DM). It provides the highly efficient production of an epithermal neutron beam with an optimized neutron energy spectrum range of 0.1~10 keV. With a 2-mA 10-MeV proton beam from the accelerator, the irradiation port epithermal neutron flux is higher than 1 × 109 n/cm2⋅s. Comprehensive verification and validation of the system have been conducted with the measurement of both proton and neutron beam characteristics. Significant therapeutic effects from BNCT have been confirmed by DM in both in vitro and in vivo non-clinical trials. Further, during exposure to epithermal neutrons, all other unintended radiation is controlled to levels meeting International Atomic Energy Agency (IAEA) recommendations. Recently, the Korean FDA has accepted an investigational new drug (IND) and the first-in-human clinical trial of BNCT is now being prepared. This paper introduces the principles of BNCT and accelerator-based neutron sources for BNCT and reports the recent advances of DM A-BNCT facility which is the main part of this paper.

The article gives an introductory summary of our recent results from the perspective of the new conceptual notion of noncommutative values of quantum observables, where basic quantum mechanics is seen a theory of particle dynamics that is intrinsically noncommutative. Real numbers as an algebra is really an abstract mathematical model for the description of values of physical quantities. Quantum mechanics illustrates the limitation of that perspective. The noncommutative values preserve the algebraic relations among the observables in their values. Such a value contains the complete information the theory presents for an observable on a given state. All physical quantities, including coordinates of the physical space for describing the location of a particle take definite noncommutative values.

The successful preparation of superconducting alkali fulleride (AxC60, A = K, Rb, Cs) films using state-of-the-art molecular beam epitaxy overcomes the disadvantages of the air-sensitivity and phase separation in bulk AxC60, enabling for the first time a direct investigation of the superconductivity in alkali fullerides on the molecular scale. In this paper, we briefly review recent cryogenic scanning tunneling microscopy results of the structural, electronic, and superconducting properties of the fcc AxC60 films grown on graphitized SiC substrates. Robust s-wave superconductivity is revealed against the pseudogap, electronic correlation, non-magnetic impurities, and merohedral disorder. By controlling the alkali-metal species, film thickness, and electron doping, we systematically tune the C60x− orientational orderings and superconductivity in AxC60 films and then complete a unified phase diagram of superconducting gap size vs electronic correlation and doping. These investigations are conclusive and elucidated that the s-wave superconductivity retains in alkali fullerides despite of the electronic correlation and presence of pseudogap.

There had been remarkable progress in developing third-generation electron storage rings as the main sources of very bright photon beams. Fourth-generation storage rings based on the multi-bend achromat lattice concept may be able to surpass the brightness and coherence that are attained using present third-generation storage rings. In this paper, we survey ongoing work around the world to develop concepts and designs for fourth-generation electron storage rings.

Neutron stars are cosmic laboratories to study dense matter in quantum chromodynamics (QCD). The observable mass-radius relations of neutron stars are determined by QCD equations of state and can reflect the properties of QCD phase transitions. In the last decade, there have been historical discoveries in neutron stars; the discoveries of two-solar mass neutron stars and neutron star merger events, which have imposed tight constraints on equations of state. While a number of equations of state are constructed to satisfy these constraints, a theoretical challenge is how to reconcile those constructions with the microphysics expected from the hadron physics and in-medium calculations. In this short article, we briefly go over recent observations and discuss their implications for dense QCD matter, referring to QCD constraints in the low- and high-density limits, QCD-like theories, and lattice QCD results for baryon-baryon interactions.