The very high light-harvesting efficiency of natural photosynthetic systems in conjunction with recent experiments, which showed quantum-coherent energy transfer in photosynthetic complexes, raised questions regarding the presence of non-trivial quantum effects in photosynthesis. Grover quantum search, quantum walks, and entanglement have been investigated as possible effects that lead to this efficiency. Here we explain the near-unit photosynthetic efficiency without invoking non-trivial quantum effects. Instead, we use non-equilibrium Green's functions, a mesoscopic method used to study transport in nano-conductors to compute the transmission function of the Fenna-Matthews-Olson (FMO) complex using an experimentally derived exciton Hamiltonian. The chlorosome antenna and the reaction center play the role of input and output contacts, connected to the FMO complex. We show that there are two channels for which the transmission is almost unity. Our analysis also revealed a dephasing-driven regulation mechanism that maintains the efficiency in the presence of varying dephasing potentials.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5471171 | PMC |
http://dx.doi.org/10.1007/s10867-017-9449-4 | DOI Listing |
Rev Sci Instrum
January 2025
Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala 695551, India.
Quantum technology exploits fragile quantum electronic phenomena whose energy scales demand ultra-low electron temperature operation. The lack of electron-phonon coupling at cryogenic temperatures makes cooling the electrons down to a few tens of millikelvin a non-trivial task, requiring extensive efforts on thermalization and filtering high-frequency noise. Existing techniques employ bulky and heavy cryogenic metal-powder filters, which prove ineffective at sub-GHz frequency regimes and unsuitable for high-density quantum circuits such as spin qubits.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Department of Physics, Indian Institute of Technology Hyderabad, Kandi, Medak 502 284, Telangana, India.
The topological properties of the A15-type compound TiPd reveal a complex landscape of multi-fold fermionic and bosonic states, as uncovered through calculations within the framework of density functional theory (DFT). The electronic band structure shows multi-fold degenerate crossings at the high-symmetry point R near the Fermi level, which evolves into 4-fold and 8-fold degenerate fermionic states upon the introduction of spin-orbit coupling (SOC). Likewise, the phononic band structure features multi-fold degenerate bosonic crossings at the same R point.
View Article and Find Full Text PDFNature
January 2025
Department of Physics and Astronomy, Rice University, Houston, TX, USA.
Nat Commun
January 2025
TCM Group, Cavendish Laboratory, Department of Physics, Cambridge, UK.
We report on a class of gapped projected entangled pair states (PEPS) with non-trivial Euler topology motivated by recent progress in band geometry. In the non-interacting limit, these systems have optimal conditions relating to saturation of quantum geometrical bounds, allowing for parent Hamiltonians whose lowest bands are completely flat and which have the PEPS as unique ground states. Protected by crystalline symmetries, these states evade restrictions on capturing tenfold-way topological features with gapped PEPS.
View Article and Find Full Text PDFJ Chem Phys
December 2024
Max Planck Institute for the Structure and Dynamics of Matter and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany.
In this work, we theoretically explore whether a parity-violating/chiral light-matter interaction is required to capture all relevant aspects of chiral polaritonics or if a parity-conserving/achiral theory is sufficient (e.g., long-wavelength/dipole approximation).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!