A5074343703- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
- Organic Electronics and Photovoltaics
- Molecular Junctions and Nanostructures
- Physics of Superconductivity and Magnetism
- Photochemistry and Electron Transfer Studies
- Photosynthetic Processes and Mechanisms
- Photoreceptor and optogenetics research
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Machine Learning in Materials Science
- Quantum, superfluid, helium dynamics
- Quantum Computing Algorithms and Architecture
- Organic Light-Emitting Diodes Research
- Conducting polymers and applications
- Organic and Molecular Conductors Research
- Magnetic Properties of Alloys
- Spectroscopy and Laser Applications
- Bone and Dental Protein Studies
- DNA and Nucleic Acid Chemistry
- Cardiac Valve Diseases and Treatments
- Rare-earth and actinide compounds
- dental development and anomalies
- Graphene research and applications
- Molecular spectroscopy and chirality
National Institutes for Quantum Science and Technology
2021-2025
The University of Tokyo
1999-2023
Chuo University
2022
Institute for Molecular Science
2017-2021
Harvard University
2012-2016
Kyoto University
2002-2016
Kobe University
2006-2012
Rikkyo University
2012
Japan Science and Technology Agency
2006-2009
Hiroshima University
2001
Phototrophic organisms such as plants, photosynthetic bacteria and algae use microscopic complexes of pigment molecules to absorb sunlight. Within the light-harvesting complexes, which frequently have several functional structural subunits, energy is transferred in form molecular excitations with very high efficiency. Green sulfur are considered be amongst most efficient organisms. Despite multiple experimental theoretical studies these physical origin robust transfer their not well...
${\mathrm{CuO}}_{2}$ out-of-plane resistivity $({\ensuremath{\rho}}_{c})$ and in-plane $({\ensuremath{\rho}}_{a}$ ${\ensuremath{\rho}}_{b})$ measurements were carried out on ${\mathrm{Bi}}_{2.1\ensuremath{-}x}{\mathrm{Pb}}_{x}{\mathrm{Sr}}_{1.8}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{y}$ single crystals with various Pb content, $0<~x<~0.6$. The absolute value of ${\ensuremath{\rho}}_{c}$ in the normal state systematically decreased increasing whereas no appreciable change was observed...
Chlorosomes are likely the largest and most efficient natural light-harvesting photosynthetic antenna systems. They composed of large numbers bacteriochlorophylls organized into supramolecular aggregates. We explore microscopic origin fast excitation energy transfer in chlorosome using recently resolved structure atomistic-detail simulations. Despite dynamical disorder effects on electronic transitions bacteriochlorophylls, our simulations show that exciton delocalizes over entire aggregate...
Regurgitant flow was analysed in 40 cases of mitral regurgitation, using combined ultrasonic pulsed Doppler technique and two dimensional echocardiography. Abnormal signals indicative regurgitant were detected reference to the image long axis view heart short at level orifice. The overall direction into left atrium clearly seen 28 cases, localisation orifice 38 cases. In with valve prolapse anterior leaflet or posterior directed posteriorly anteriorly, respectively. occurred anterolateral...
Phycobilisomes are antenna protein complexes in cyanobacteria and red algae. In phycobilisomes, energy transfer is unidirectional with an extremely high quantum efficiency close to unity. We investigate intraprotein relaxation coherence of constituent chromoproteins allophycocyanin (APC) two kinds C-phycocyanin (CPC) phycobilisomes using two-dimensional electronic spectroscopy (2D-ES). These have similar adjacent pairs pigments $\alpha$84 $\beta$84, which excited delocalized exciton states....
Chlorosomes are efficient light-harvesting antennas containing up to hundreds of thousands bacteriochlorophyll molecules. With massively parallel computer hardware, we use a nonperturbative stochastic Schrödinger equation, while including an atomistically derived spectral density, study excitonic energy transfer in realistically sized chlorosome model. We find that fast short-range delocalization leads robust long-range due the antennae's concentric-roll structure. Additionally, discover...
We developed the fragment-based method for calculating nonlocal excitations in large molecular systems. This is based on multilayer fragment orbital and configuration interaction single (CIS) wave function using localized orbitals. The excited-state whole system described as a superposition of state functions (CSFs) intrafragment interfragment charge-transfer excitations. formulation calculations singlet Hamiltonian matrix elements CSFs are presented detail. efficient approximation schemes...
Phycobilisomes are antenna protein complexes in cyanobacteria and red algae. In phycobilisomes, energy transfer is unidirectional with an extremely high quantum efficiency close to unity. We investigate intraprotein relaxation coherence of constituent chromoproteins allophycocyanin (APC) two kinds C-phycocyanin (CPC) phycobilisomes using two-dimensional electronic spectroscopy. These produced by Escherichia coli expression system have similar adjacent pairs pigments α84 β84, which excited...
Charge-transfer states in organic semiconductors play crucial roles processes such as singlet fission and exciton dissociation at donor/acceptor interfaces. Recently, a time-resolved spectroscopy study of dinaphtho[2,3-b:2'3'-f]thieno[3,2-b]-thiophene (DNTT) thin films provided evidence for the formation mixed Frenkel charge-transfer excitons after photoexcitation. Here, we investigate optical properties excitation dynamics DNTT by combining ab initio calculations stochastic Schrödinger...
Uncovering the mystery of efficient and directional energy transfer in photosynthetic organisms remains a critical challenge quantum biology. Recent experimental evidence theory developments indicate significance features molecular vibrations assisting transfer, which provides possibility manipulating process by controlling vibrations. Here, we propose theoretically demonstrate manipulation using vibrational strong coupling between state Fenna–Matthews–Olson (FMO) complex vacuum an optical...
Herein, we present a fragment-based approach for calculating the charged and neutral excited states in molecular systems, based on many-body Green's function method within GW approximation Bethe-Salpeter equation (BSE). The implementation relies expansion of total irreducible polarizability basis fragment orbitals. quasi-particle energies complex environments are obtained by calculation target plus induced polarization contributions surrounding fragments at static Coulomb-hole screened...
We have developed an ab initio path integral molecular dynamics method based on the fragment orbital method. This “FMO-PIMD” can treat both nuclei and electrons quantum mechanically, is useful to simulate large hydrogen-bonded systems with high accuracy. After a benchmark calculation for water monomer, trimer glycine pentamer been studied using FMO-PIMD investigate nuclear effects structure interactions. The applicability of present approach demonstrated through number test calculations.
We present a fragment-based many-body Green's function method suitable for treating large molecular systems in heterogeneous polarizable environments. The total system is approximated from fragment functions and expanded up to two-body terms. screened Coulomb potential the sum of intrafragment density-response functions, with interfragment polarization terms being neglected. approximations lead expansion self-energy. This essentially equivalent Fock matrix orbital method. To handle systems,...
Integral equation theories provide an efficient route for computing the solvation free energy (SFE) of molecular systems in water. The accuracy those is usually tested against small molecules via comparison SFE with reference data. However, tests larger nanometer regime are scarce literature despite recent applications to such systems. Here, we thus study and validity a commonly used integral theory, namely, three-dimensional interaction site model (3D-RISM), by considering following...
Predicting the charge-transfer (CT) excited states across donor/acceptor (D/A) interface is essential for understanding charge photogeneration process in an organic solar cell. Here, we present a fragment-based GW implementation that can be applied to D/A structure and thus enables accurate determination of CT states. The based on fragmentation approximation polarization function combined Coulomb-hole plus screened exchange approximations self-energies. demonstrated by application...
We perform a beat-frequency-resolved analysis for two-dimensional electronic spectroscopy using high-speed and stable 2D spectrometer few-cycle visible laser pulses to disentangle the vibrational coherences in an artificial fluorescent protein. develop highly ultrashort light source that generates 5.3-fs with pulse energy of 4.7 µJ at repetition rate 10 kHz multi-plate compression filamentation gas cell. The above-5.3-fs together multichannel detector enable us measure series spectra, which...