김은종 교수

While designing the energy-momentum relation of photons is key to many linear, nonlinear, and quantum optical phenomena, a new set of light-matter properties may be realized by employing the topology of the photonic bath itself. In this work we experimentally investigate the properties of superconducting qubits coupled to a metamaterial waveguide based on a photonic analog of the Su-Schrieffer-Heeger model. We explore topologically induced properties of qubits coupled to such a waveguide, rangin

Bioinspired piezoelectric nanogenerators based on phage nanopillars are inceptively demonstrated, and the electrical power from phage nanopillars holds promise for the development of implantable and wearable electronics.

Embedding tunable quantum emitters in a photonic bandgap structure enables control of dissipative and dispersive interactions between emitters and their photonic bath. Operation in the transmission band, outside the gap, allows for studying waveguide quantum electrodynamics in the slow-light regime. Alternatively, tuning the emitter into the bandgap results in finite-range emitter-emitter interactions via bound photonic states. Here, we couple a transmon qubit to a superconducting metamaterial w

Synthesizing many-body quantum systems with various ranges of interactions facilitates the study of quantum chaotic dynamics. Such extended interaction range can be enabled by using nonlocal degrees of freedom such as photonic modes in an otherwise locally connected structure. Here, we present a superconducting quantum simulator in which qubits are connected through an extensible photonic-bandgap metamaterial, thus realizing a one-dimensional Bose-Hubbard model with tunable hopping range and on-

Moisture content influences physiological characteristics of microbes and physical structure of solid matrices during composting of animal manure. If moisture content is maintained at a proper level, aerobic microorganisms show more active oxygen consumption during composting due to increased microbial activity. In this study, optimum moisture levels for composting of two bedding materials (sawdust, rice hull) and two different mixtures of bedding and beef manure (BS, Beef cattle manure+sawdust;

We propose a superconducting electrical circuit that simulates a quadratic optomechanical system. A capacitor placed between two transmission-line (TL) resonators acts like a semitransparent membrane, and a superconducting quantum interference device (SQUID) that terminates a TL resonator behaves like a movable mirror. Combining these circuit elements, it is possible to simulate a quadratic optomechanical coupling whose coupling strength is determined by the coupling capacitance and the tunable

The effect of thermal pretreatment conditions on hydrolysis characteristics of dairy manure and sawdust mixtures has been evaluated. Thermal pretreatment temperature varied between 35 and <TEX>$120^{\circ}C$</TEX> and the period of the treatment changed between 30 and 1440min (24h). As thermal pretreatment temperature and duration increased, organic material solublization rates were improved. Maximum solubilizations of chemical oxygen demand (SCOD), carbohydrates, and volatile fatty acids(VFAs)

Blocking the near-infrared region (NIR) is indispensable for saving energy consumed to maintain the interior temperature in buildings. However, simultaneously enhancing transmission in visible light and blocking in the NIR remains challenging. Here, we theoretically demonstrate a transparent all-dielectric metasurface selectively blocking the NIR by using TiO 2 nanocylinders and an indium tin oxide (ITO) layer. The ITO layer is implemented as a back reflector because ITO is transparent in visibl

A superconducting quantum circuit coupled to a tailored waveguide reservoir provides a platform for exploring non-Markovian quantum-optical dynamics, in which the reservoir maintains a memory of past events.

Waveguide quantum electrodynamics studies photon-mediated interactions of quantum emitters in a one-dimensional radiation channel. Although signatures of such interactions have been observed previously in a variety of physical systems, observation of coherent cooperative dynamics has been obscured by radiative decay of atoms into the waveguide. Employing transmon qubits as artificial atoms coupled to a microwave coplanar waveguide, here we observe dynamical oscillations in an open system where a

Abstract Nearly all network applications rely on the global Internet routing infrastructure to compute routes and deliver packets. Unfortunately, false Internet routes can be maliciously introduced with relative ease into the routing infrastructure. This is because Border Gateway Protocol (BGP), the Internet’s global routing protocol, lacks basic authentication and monitoring functionalities. If false routes are introduced, it can lead to total collapse of packet forwarding leading to denial of

The DNS Security Extensions (DNSSEC) were developed to add origin authentication and integrity. DNSSEC defined a public key infrastructure over DNS tree hierarchy for the public key validation. In DNSSEC, a parent zone authenticates public keys of its child zones. The authentication hierarchy is broken when a parent does not support DNSSEC. This paper proposes an effective mechanism to overcome this partial deployment problem. Our solution uses a public bulletin board for zones to post their DNS