김도헌 교수

Broadband detection of mid-infrared (IR) photons extends to advanced optoelectronic applications such as imaging, sensing, and telecommunications. While graphene offers an attractive platform for broadband visible/IR photodetection, previous efforts to improve its responsivity, for example, by integrating light-absorbing colloids or waveguide or antenna fabrication, were achieved at the cost of reduced photon detection bandwidth. In this work, we demonstrate room-temperature operation of a novel

Bioinspired sulfur-doped carbon dots with strong NIR absorbance are prepared from Camellia japonica flowers via a facile hydrothermal method for enhancing photothermal cancer therapy.

We measure the temperature-dependent carrier density and resistivity of the topological surface state of thin exfoliated ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$ in the absence of bulk conduction. When the gate-tuned chemical potential is near or below the Dirac point, the carrier density is strongly temperature-dependent, reflecting thermal activation from the nearby bulk valence band, while, above the Dirac point, unipolar $n$-type surface conduction is observed with negligible thermal activation

In the development of hydrogen-based technology, a key challenge is the sustainable production of hydrogen in terms of energy consumption and environmental aspects. However, existing methods mainly rely on fossil fuels due to their cost efficiency, and as such, it is difficult to be completely independent of carbon-based technology. Electrochemical hydrogen production is essential, since it has shown the successful generation of hydrogen gas of high purity. Similarly, the photoelectrochemical (P

We report a single-shot-based projective readout of a semiconductor hybrid qubit formed by three electrons in a GaAs double quantum dot. Voltage-controlled adiabatic transitions between the qubit operations and readout conditions allow high-fidelity mapping of quantum states. We show that a large ratio both in relaxation time vs tunneling time (≈50) and singlet-triplet splitting vs thermal energy (≈20) allows energy-selective tunneling-based spin-to-charge conversion with a readout visibility of

This paper models a preferred skin color area with a set of ellipses according to the average luminance of skin and proposes an effective method for skin color reproduction by introducing the affine transform from the skin color ellipse to the preferred skin color ellipse. Also the contour reduction algorithm is described to remove false contours caused by skin color transformation. The visual test is performed to decide the most appropriate preferred skin color for the proposed transformation.

Abstract Efficient and cost‐effective electrocatalysts that can operate across a wide range of pH conditions are essential for green hydrogen production. Inspired by biological systems, Fe 7 S 8 nanoparticles incorporated on polydopamine matrix electrocatalyst were synthesized by co‐precipitation and annealing process. The resulting Fe 7 S 8 /C electrocatalyst possesses a three‐dimensional structure and exhibits enhanced electrocatalytic performance for hydrogen production across various pH cond