Dynamically protected erasure qubit via low-frequency charge driving

Kavli Affiliate: Irfan Siddiqi | Summary:Dynamical protection via strong driving can enable resilient quantum processing on imperfect physical hardware. However, the practical utility of such schemes is frequently limited by parasitic processes such as drive-induced dephasing and leakage. Here, we demonstrate that sub-GHz charge driving of superconducting Kerr oscillators (KOs) in the transmon regime circumvents […]


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Ambipolar metal-insulator transition in bilayer MoSe2

Kavli Affiliate: Archana Raja| Summary:When Coulomb interactions dominate kinetic energy, dilute two-dimensional carriers form a Wigner solid. Both its melting and disorder-driven localization can drive density-tuned metal-insulator transitions, but their relative roles and interplay have been debated for decades. Atomically thin semiconductors offer a new test because transport and scanning tunneling microscopy can probe the […]


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Synthesis of Metal-Semiconductor Heterojunctions in Single Graphene Nanoribbons

Kavli Affiliate: Michael Crommie | Summary:Graphene nanoribbons (GNRs) are a highly tunable class of one-dimensional (1D) quantum materials that can be fabricated through bottom-up synthesis. Precise control over GNR band gaps and band-edge alignments has established them as a promising nanoelectronics platform, but forming high-quality electronic interfaces remains challenging. Here we combine sequential on-surface synthesis […]


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Normal-ordered perturbative expansion for matter systems interacting with continuous-mode quantum photon fields

Kavli Affiliate: Birgitta Whaley | Summary:We develop a normal-ordered perturbative expansion method to compute the reduced dynamics of a matter system interacting with a general continuous-mode photon field state. In this expansion, all field correlation functions are automatically normal-ordered, while the free evolution is modified by spontaneous emission. Our normal-ordered expansion elucidates the physical meaning […]


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Input-output formulation of quantum light spectroscopy

Kavli Affiliate: Birgitta Whaley | Summary:We develop an input-output formulation of quantum light spectroscopy (QLS) by combining the input-output theory, commonly used in quantum optics, with the perturbative expansion method for nonlinear spectroscopy, commonly used in chemical physics. The use of the input-output relation provides physical intuition for how matter systems alter the photon input […]


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Minor Structural Differences Tune Functional Specialization of Antenna Subunits in the PSII Energy Transfer Network

Kavli Affiliate: Graham Fleming | Summary:Photosystem II (PSII) contains a diverse array of pigment-protein subunits with specialized roles in the antenna network. We investigate the functional significance of this subunit diversity in two structurally similar yet functionally distinct PSII subunits: minor light-harvesting complex CP29 and major light-harvesting complex LHCII. We combine two-dimensional electronic-vibrational spectroscopy with […]


Continue.. Minor Structural Differences Tune Functional Specialization of Antenna Subunits in the PSII Energy Transfer Network

(Sub)nanoscale Visualization of Reconstruction-Driven Moiré Exciton Localization and Delocalization

Kavli Affiliate: Archana Raja| Summary:Spectral fingerprints in optical absorption and emission have typically been used as a signature of exciton localization in twisted moiré bilayers. However, the mechanism by which excitons become confined to specific stacking sites and their associated optical signature is experimentally unresolved. Here, we directly visualize in real space how tuning the […]


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Reduced scaling implementation of the coupled cluster-based static embedding method, MPCC with density fitting

Kavli Affiliate: Birgitta Whaley | Summary:An improved algorithm to implement our previously proposed static quantum embedding method MPCC (J. Chem. Phys. 161, 164107 (2024)) is presented. It uses the density-fitting (DF) approximation for the electron-repulsion integrals (ERIs) across all layers of the embedding method: the low-level method, the screened interaction, and the high-level method. Additionally, […]


Continue.. Reduced scaling implementation of the coupled cluster-based static embedding method, MPCC with density fitting

Reduced scaling implementation of the coupled cluster-based static embedding method, MPCC with density fitting

Kavli Affiliate: Birgitta Whaley | Summary:An improved algorithm to implement our previously proposed static quantum embedding method MPCC (J. Chem. Phys. 161, 164107 (2024)) is presented. It uses the density-fitting (DF) approximation for the electron-repulsion integrals (ERIs) across all layers of the embedding method: the low-level method, the screened interaction, and the high-level method. Additionally, […]


Continue.. Reduced scaling implementation of the coupled cluster-based static embedding method, MPCC with density fitting

Subnanometer thermodynamic overlayers on bimetallic nanoparticles

Kavli Affiliate: Kristin Persson | Summary:Nanoparticle properties are governed by their surfaces, yet their atomic-scale surface structures remain challenging to predict. Here, we report that bimetallic nanoparticles can form a thermodynamically controlled "shell-dimer" architecture in which one metal forms an overlayer only a few atomic layers thick on another. Using Au-Rh as a model system, […]


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