The observed prevalence of oscillatory signals in the spectroscopy biological light-harvesting complexes at ambient temperatures has led to a search for mechanisms supporting coherent transport through larger molecules noisy environments. We demonstrate generic mechanism long-lasting electronic coherence up 0.3 ps temperature 277 K. relies on two properties spectral density: (i) large dissipative coupling continuum higher-frequency vibrations required efficient and (ii) small slope density...

Excitonic models of light-harvesting complexes, where the vibrational degrees freedom are treated as a bath, commonly used to describe motion electronic excitation through molecule. Recent experiments point toward possibility memory effects in this process and require one consider time nonlocal propagation techniques. The hierarchical equations (HEOM) were proposed by Ishizaki Fleming site-dependent reorganization dynamics protein environments ( J. Chem. Phys. 2009 , 130 234111 ), which...

Recent experimental observations of time-dependent beatings in the two-dimensional echo-spectra light-harvesting complexes at ambient temperatures have opened up question whether coherence and wave-like behaviour play a significant role photosynthesis. We carry out numerical study absorption Fenna–Matthews–Olson (FMO) complex Chlorobium tepidum analyse requirements theoretical model needed to reproduce calculated spectra. The energy transfer FMO pigment–protein is theoretically described by...

The accurate simulation of excitonic energy transfer in molecular complexes with coupled electronic and vibrational degrees freedom is essential for comparing system parameters obtained from ab initio methods measured time-resolved spectra. Several exact computing the exciton dynamics within a density-matrix formalism are known but restricted to small systems less than 10 sites due their computational complexity. To study larger systems, we adapt extend hierarchical equation motion (HEOM)...

We have found evidence that water plugs in hydrophilic nanochannels can be at significant negative pressure due to tensile capillary forces. The of induces bending the thin channel capping layer, which results a visible curvature liquid meniscus. From detailed analysis meniscus curvature, amount calculated and used determine liquid. For silicon oxide 108 nm height, 17 ± 10 bar was found. absence cavitation such large pressures is explained by fact critical radius for seeding cavities...

We reconstruct the temporal evolution of source distribution for four major gas species H2O, CO2, CO, and O2 on surface comet 67P/Churyumov-Gerasimenko during its 2015 apparition. The analysis applies an inverse coma model fits to data between August 6th 2014 September 5th 2016 measured with Double Focusing Mass Spectrometer (DFMS) Rosetta Orbiter Ion Neutral Analysis (ROSINA) COmet Pressure Sensor (COPS). spatial sources their variation allows one construct maps emissions evaluate...

The coma of comet 67P/Churyumov-Gerasimenko has been probed by the Rosetta spacecraft and shows a variety different molecules. ROSINA COmet Pressure Sensor Double Focusing Mass Spectrometer provide in-situ densities for many volatile compounds including 14 gas species H2O, CO2, CO, H2S, O2, C2H6, CH3OH, H2CO, CH4, NH3, HCN, C2H5OH, OCS, CS2. We fit observed during entire mission between August 2014 September 2016 to an inverse model. retrieve surface emissions on cometary shape with 3996...

ABSTRACT SU‐8 is a photoplastic polymer with wide range of possible applications in microtechnology. Cantilevers designed for atomic force microscopes were fabricated SU‐8. The mechanical properties these cantilevers investigated using two microscale testing techniques: contact surface profilometer beam deflection and static load at point on the specially test machine. Young's modulus value from methods approximately 2–3 GPa.

The prevalence of long-lasting oscillatory signals in two-dimensional (2D) echo spectroscopy light-harvesting complexes has led to a search for possible mechanisms. We investigate how two causes are intertwined: (i) electronic coherences supporting delocalized wavelike motion and (ii) narrow bands the vibronic spectral density. To disentangle contributions, we introduce time-windowed Fourier transform signal amplitude. find that 2D spectra can be dominated by excitations pathways which...

Starting from several monthly data sets of Rosetta's COmetary Pressure Sensor we reconstruct the gas density in coma around comet 67P/Churyumov-Gerasimenko. The underlying inverse model is constructed by fitting ten thousands measurements to potential sources distributed across entire nucleus surface. ensuing self-consistent solution for and surface activity reproduces temporal spatial variations seen periods with Pearson correlation coefficients 0.93 higher. For different seasonal...

In many physical situations involving diverse length scales, waves or rays representing them travel through media characterized by spatially smooth, random, modest refactive index variations. "Primary" diffraction (by individual sub-wavelength features) is absent. Eventually the weak refraction leads to imperfect focal "cusps". Much later, a statistical regime momentum diffusion manifested. An important intermediate often overlooked, one that diffusive only in an ensemble sense. Each...

Aims . This paper focuses on how insolation affects the nucleus of comet 67P/Churyumov-Gerasimenko over its current orbit. We aim to better understand thermal environment nucleus, in particular surface temperature variations, erosion, relationship with topography, and interior for location volatile species (H 2 O CO ). Methods have developed two models calculate subsurface temperatures 67P 6.45-year The first model, high resolution (300 000 facets), calculates temperatures, taking shadows...

We examine the spatial distribution of electrons generated by a fixed energy point source in uniform, parallel electric, and magnetic fields. This problem is simple enough to permit analytic quantum semiclassical solution, it harbors rich set features which find their interpretation unusual interesting properties classical motion electrons: For instance, number interfering trajectories can be adjusted this system, turning surfaces contain complex array singularities. perform comprehensive...

We investigate the propagation of wave packets on graphene in a perpendicular magnetic field and appearance collapses revivals time evolution an initially localized packet. The wave-packet differs drastically from one electron gas shows rich revival structure similar to dynamics highly excited Rydberg states. present novel numerical scheme order solve effective single-particle Dirac–Hamiltonian show how collapse is affected by presence disorder. Our method general interest for solution Dirac...

Abstract The microphysical structure of the lunar regolith provides information on geologic history Moon. We used remote sensing measurements thermal emission and a thermophysical model to determine properties regolith. expand upon previous investigations by developing model, which more directly simulates properties, such as grain size volume filling factor. modeled temperatures are matched with surface measured Diviner Lunar Radiometer Experiment board Reconnaissance Orbiter. maria...

Localized scattering phenomena may result in the formation of stationary matter waves originating from a compact region physical space. Mathematically, such are advantageously expressed terms quantum sources that introduced into Schrödinger equation. The source formalism yields direct access to wavefunction, particle distribution and total current. As an example, we study emission three-dimensional Gaussian homogeneous force field. This model describes behaviour atom laser supplied by ideal...

An alternative description of quantum scattering processes rests on inhomogeneous terms amended to the Schr\"odinger equation. We detail structure sources that give rise multipole waves definite angular momentum, and introduce pointlike as their limiting case. obtain results for ballistic in an external uniform force field, where we provide analytical solutions both integrated particle flux. Our theory directly applies p-wave photodetachment electric field. Furthermore, illustrating effects...

Time- and frequency-resolved optical signals provide insights into the properties of light-harvesting molecular complexes, including excitation energies, dipole strengths orientations, as well in exciton energy flow through complex. The hierarchical equations motion (HEOM) a unifying theory, which allows one to study combined effects system-environment dissipation non-Markovian memory without making restrictive assumptions about weak or strong couplings separability vibrational electronic...

Cometary activity affects the orbital motion and rotation state due to sublimation induced forces. The availability of precise rotation-axis orientation position data from Rosetta mission allows one accurately determine outgassing comet Churyumov-Gerasimenko/67P. We derive observed non-gravitational acceleration 67P directly spacecraft trajectory. From we recover diurnal variations study a possible delay response with respect peak solar illumination. This us compare expectations based on...

Time-resolved spectroscopy provides the main tool for analyzing dynamics of excitonic energy transfer in light-harvesting complexes. To infer time-scales and effective coupling parameters from experimental data requires to develop numerical exact theoretical models. The finite duration laser-molecule interactions reorganization process during exciton migration affect location strength spectroscopic signals. We show that non-perturbative hierarchical equations motion (HEOM) method captures...

We study the quantal motion of electrons emitted by a pointlike monochromatic isotropic source into parallel uniform electric and magnetic fields. The two-path interference pattern in emerging electron wave due to force is modified lens effect which periodically focuses beam narrow filaments along symmetry axis. There, four classical paths interfere. With increasing energy, current distribution changes from quantum regime governed uncertainty principle, an intricate spatial that yields...