klaurent – Page 6 – Kavli Institute Pre-Print Publications

Distinguishing the origin of cosmic birefringence: dark energy, dark matter, and neutrino asymmetry

Posted by klaurent October 2, 2026October 12, 2026Tokyo

Kavli Affiliate: Eiichiro Komatsu | Summary:Cosmic birefringence, the isotropic rotation of the plane of linear polarization of photons from sources at cosmological distances, can be generated by different parity-violating mechanisms. While the net rotation angle of a single polarized source carries little information about its physical origin, sources at various redshifts $z$ can be used […]

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A Refined Analytic Oblate–Schwarzschild Model for Thermal X-Ray Pulse Profiles of Rotating Neutron Stars

Posted by klaurent October 2, 2026October 12, 2026Peking

Kavli Affiliate: Renxin Xu | Summary:Thermal X-ray pulse profiles constrain neutron-star masses and radii through the effects of gravitational light bending and rotation on surface emission. The precision anticipated from the enhanced X-ray Timing and Polarimetry (eXTP) mission motivates more accurate analytic light-bending formulae that retain the efficiency needed for repeated model evaluations. We derive […]

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Synthesis of Metal-Semiconductor Heterojunctions in Single Graphene Nanoribbons

Posted by klaurent October 1, 2026October 12, 2026Berkeley

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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Independent Amplitude and Phase Modulation in Active Transmissive Metasurfaces via Complex Permittivity Tuning

Posted by klaurent October 1, 2026October 12, 2026Caltech

Kavli Affiliate: Harry Atwater | Summary:Active metasurfaces are a promising platform for spatial light modulators (SLMs) in applications such as holography, beam shaping, and light detection and ranging (LiDAR), as they enable dynamic control over the amplitude and phase of light at subwavelength scales. Among these, transmissive metasurfaces offer a compact alternative to conventional SLMs, […]

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Parallax Depth Sectioning and 3D Reconstruction in 4D-STEM

Posted by klaurent October 1, 2026October 12, 2026Cornell

Kavli Affiliate: David Muller | Summary:Three-dimensional (3D) information is encoded in four-dimensional scanning transmission electron microscopy (4D-STEM) through parallax between the virtual images formed at each detector pixel. In this paper we connect the encoding and retrieval of depth-dependent information in 4D-STEM to two other widely-used 3D imaging methods, tomography and light-field photography, and derive […]

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Strongly coupled ultracompressed self-cavity plasmon polaritons at millikelvin temperatures

Posted by klaurent September 30, 2026October 12, 2026Cornell

Kavli Affiliate: Debanjan Chowdhury | Summary:Van der Waals heterostructures exhibit self-cavity resonances from sub-terahertz to terahertz frequencies and thus offer an attractive route toward realizing cavity-modified phases of matter. Spectroscopy of such systems calls for high frequency resolution at millikelvin temperatures, which is extremely challenging with existing methods. Here we demonstrate a new platform for […]

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Which Milky Way Streams Make the Best Dark Matter Detectors?

Posted by klaurent September 30, 2026October 12, 2026Stanford

Kavli Affiliate: Risa Wechsler | Summary:The abundance and properties of low-mass dark matter subhalos can be inferred by measuring the density and velocity structure of stellar streams, testing physical models of dark matter. Which streams make the most promising dark matter detectors, and which subhalos would they encounter? We use the semi-analytic model galacticus to […]

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Design of Mechanically Compliant Membrane Reflectors for Giant Optical Phase Nonlinearity

Posted by klaurent September 30, 2026October 12, 2026Caltech

Kavli Affiliate: Harry Atwater | Summary:Optical nonlinearities arise when the response of a photonic system depends on light intensity. Radiation pressure can create such a nonlinearity by moving a mechanically compliant reflector, thereby shifting the phase of the reflected light. Based on measured properties, we predict a giant phase responsivity of 263 rad W$^-1$ and […]

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Interpreting the High-Recoil LUX-ZEPLIN Event with Bino-/Singlino-like and Higgsino Dark Matter

Posted by klaurent September 30, 2026October 12, 2026Chicago

Kavli Affiliate: Carlos Wagner | Summary:The LUX-ZEPLIN (LZ) experiment has recently reported a nuclear-recoil candidate at $E_Rsimeq248$ keV. We study two supersymmetric interpretations based on distinct neutralino couplings to the $Z$ boson. In the elastic case, a bino- or singlino-like neutralino scatters through a diagonal axial $Z$ coupling set by the Higgsino asymmetry $X=|N_13|^2-|N_14|^2$ rather […]

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Improved Constraints on Cosmic Microwave Background Circular Polarization with CLASS

Posted by klaurent September 30, 2026October 12, 2026Chicago

Kavli Affiliate: Jeffrey McMahon | Summary:We present improved constraints on circular polarization in the cosmic microwave background (CMB) from the Cosmology Large Angular Scale Surveyor (CLASS) experiment using data at 90, 150, and 220 GHz to complement previous results based on 40 GHz data alone. We extend constraints on circular polarization from the atmosphere to […]

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