Mikhail Kats

@mickeykats.bsky.social

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Optics/photonics researcher, applied physicist, and faculty at the University of Wisconsin - Madison. Personal account + opinions Was @mickeykats on Twitter

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Comments from the editor: The last sentence of the abstract needs to be changed because it reads more like an informal recommendation than a scientific conclusion. The sentence currently reads: "If you do optical design at infrared wavelengths, we recommend that you print out the figures and stick them on your wall." Please revise it so that it provides a concise, scientific concluding statement
Air quality in Madison
daily likers vs date from https://bsky.jazco.dev/stats
Black raspberries
kalshi plot for Fable 5 restoration https://kalshi.com/markets/kxfablerestore/fable-restored/kxfablerestore-27?op_market_ticker=KXFABLERESTORE-27-26JUL07
Fig. 1. Existing and future solar- and laser-sail missions. Solar sails (driven by momentum from sunlight) and laser sails (driven by momentum from an external laser) are represented together on a distance scale. The IKAROS mission (2010), the first successful solar-sail demonstration, sailed near Venus orbit (0.7 AU from the sun). High velocity solarsail concepts envision probes reaching ~100 km/s (~20 AU/year or ~0.0003𝑐) using gravity-assist maneuvers from the sun, enabling exploration of the outer solar system and beyond the heliosphere. Another future sail concept is the laser sail, which can take advantage of existing laser technology (~1 MW of power) to enable interplanetary exploration. The most audacious proposals envision ~1 GW laser arrays that could enable interstellar travel, for example to Proxima Centauri, the Sun’s nearest star. Voyagers 1 and 2, launched in 1977, are included as benchmarks of conventional spacecraft, currently just past the heliosphere at ~100 AU. (Inset) Acceleration (𝑎) as a function of sail areal density (𝑆/𝑚)for light intensities (𝐼) between 1 kW and 1 GW. The bands represent reflectivity (𝑅) ranging from 0.1 to 1, assuming negligible absorption (𝐴). Light sails span different propulsion regimes across near-earth, solar system, and interstellar space exploration, based on different combinations of sail areal densities and driving light intensities (assuming illumination across entire sail area).
“We’ve received 5,000 responses,” Coe said. “We’re going to be able to award maybe 50 out of those 5,000 in our initial front. So, if you’re wondering how much the scientific community is interested in AI and interested in the Genesis Mission, that should be your answer.”
Statement on the US government directive to suspend access to Fable 5 and Mythos 5 Jun 12, 2026 The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees. The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance. Access to all other Anthropic models will not be affected. We received the directive from the government today at 5:21pm (ET). The letter did not provide specific details of its national security concern. Our understanding is that the government believes it has become aware of a method of bypassing, or “jailbreaking” Fable 5. We reviewed a demonstration of this specific technique being used to identify a small number of previously known, minor vulnerabilities. These vulnerabilities all appear relatively simple, and we have found that other publicly-available models are able to discover them as well without requiring a bypass.
USB floppy drive
Fifa prohibited items
Metasurfaces for neutral-atom trapping Chengyu Fang, Minjeong Kim, Mark Saffman, Jennifer T. Choy, Mikhail Kats Trapped neutral atoms are one of the leading platforms for quantum information technologies, in particular for quantum computing, but scaling them to array sizes needed for utility-scale quantum computing is a major engineering challenge. Here we review optical metasurfaces as an enabling technology that provides fine control over the phase, amplitude, and polarization of light, with pixel counts far exceeding what is available with spatial light modulators (SLMs) and other active devices. The large pixel counts have recently led to demonstrations of arrays of optical tweezers with hundreds of thousands of sites and arrays of optical bottle-beams with complex three-dimensional trapping profiles. The flexibility and scalability of optical metasurfaces provides a route towards miniaturized, integrated, and highly scalable atomic experiments and instruments.
Figure 3: Multi-functionality, miniaturization, and integration enabled by metasurfaces in atomtrapping optical systems. (a) Multi-functional metasurface for generating a MOT, combining beam splitting and polarization control to generate five cooling beams from one incident beam; adapted from [64]. (b) Polarization-multiplexed metalens, operating for two wavelengths (780 nm and 850 nm) for two orthogonal linear polarizations; adapted from [38]. (c) Wavelength-multiplexed metalens at 780 nm and 852 nm, which adds quarter-wave-plate functionality only at 852 nm; adapted from [66]. (d–g) Representative compact metasurfaces that range from sub-millimeter to a few millimeters; adapted from [28, 29, 38, 66]. (h) Schematic of bright- and dark-trap generation using a metasurface integrated inside a vacuum cell; adapted from [29]. (i) An amorphous silicon on fused silica metasurface integrated inside a vacuum glass cell to replace high-NA objective; adapted from [38]. (j) Integrated metasurface platform to launch a centimeter-scale circularly polarized beam for generating MOTs; adapted from [67]. (k) Metasurface integrated to a rubidium-vapor atomic magnetometer for balanced polarimetry in a rubidium-vapor atomic magnetometer; adapted from [68].
Figure 2: Generation of optical bottle beams. (a) Bottle-beam trap generated by destructive interference of two co-propagating Gaussian beams with different waists, stabilized by an active phase lock; adapted from [56]. (b) Single dark trap generated from an incident Gaussian beam by a ∼1-mm metasurface, optimized for high efficiency and trap quality; adapted from [57]. (c) Polarization-multiplexed metasurface that generates a bright trap for one circular polarization and a dark trap for the opposite circular polarization; adapted from [58]. (d) One-dimensional array of ten dark traps generated by a metasurface; five of the sites are shown in X-Z and Y-Z, for the optic axis along Z; adapted from [59]. (e) Two-dimensional 7 × 7 dark-trap array generated by a single metasurface, shown in X-Y (in the focal plane; left) and in X-Z (right) along the trap centers; adapted from [29]. (f) Two-dimensional array of interleaved 7 × 7 bright traps and 6 × 6 dark-trap arrays generated by a single metasurface, shown X-Y (left) and X-Z along the bright array (middle), and along the dark array (right); adapted from [29].
Figure 1: Approaches to scale neutral-atom tweezer arrays. (a) Schematic of a neutral-atom quantum computer, where atoms are trapped in an optical-tweezer array, with qubits encoded in two electronic states (|0⟩ and |1⟩). A Rydberg state (|r⟩) enables entanglement between neighboring atoms, enabling multi-qubit gates such as the CNOT shown on the right. (b) An array of 12,000 tweezer sites generated by two 1024 × 1024 SLMs (∼2 million pixels in total) using 1061 nm and 1055 nm laser, with 6,100 atoms loaded; adapted from [5]. (c) An array of 360,000 tweezer sites generated by a 3.5-mm-diameter metasurface with 114 million pixels (no atoms loaded in the device shown, although single-atom trapping was demonstrated in a smaller array reported in this work); representing the results in [27]. (d) An array of 78,400 tweezer sites generated by a single 5-mmdiameter metasurface with 106 million pixels (no atoms loaded); adapted from [28]. (e) Summary of literature on metasurfaces for atom trapping [27–30], with the number of tweezers formed as a function of the number of metasurface pixels. For reference, the record result using two SLMs is also included [5]. Dashed circles mark experimentally demonstrated metasurfaces; the remaining data points correspond to simulated designs.“Measured traps” means the traps were imaged, but atoms may not have been loaded.
Triceratops maxilla fossil
The graphs show monthly mean carbon dioxide measured at Mauna Loa Observatory, Hawaii. The carbon dioxide data on Mauna Loa constitute the longest record of direct measurements of CO2 in the atmosphere. They were started by C. David Keeling of the Scripps Institution of Oceanography in March of 1958 at a facility of the National Oceanic and Atmospheric Administration [Keeling, 1976]. NOAA started its own CO2 measurements in May of 1974, and they have run in parallel with those made by Scripps since then [Thoning, 1989]. from https://gml.noaa.gov/ccgg/trends/
Figure 1: Approaches to scale neutral-atom tweezer arrays. Panel 1d says "Panel unavailable in preprint because reprint permissions by Nature were not granted"
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"United Nations peacekeepers passing through downtown Mongbwalu this week" from https://www.nytimes.com/2026/05/30/world/africa/ebola-epicenter-congo.html?unlocked_article_code=1.mVA.ZfgE.ds-DeW3fz8J2&smid=url-share
Fig. 3. Correlation between the refractive index (n*) and the optical bandgap (Eg). For each selected material, n* was taken at the wavelength point of lowest dispersion. The Moss relation (n 4Eg = 95 eV) is also plotted, as a reference curve.
Fig. 1. Infrared-transparent materials for thin-film coatings. (a) Real part of the refractive index (n) for various candidate materials, where the wavelength regions satisfying an absorption coefficient of α < 10 cm-1 are defined as their ‘transparency window’ and plotted over the 0.2–25 µm spectral range. The materials are categorized by their chemical group. Typical thin-film deposition techniques are indicated for each material, arranged from less-epitaxial to more-epitaxial processes. Gaps in the transparency windows of a-SiO2 near 2.8 μm, a-SiN near ~3.0 μm, and a-Si near ~5.0 μm arise from O–H, N–H, and Si–H absorptions, respectively. (b) Magnified view of the highlighted region, using linear scales for both n and transparency wavelength
Screenshot from https://physics.stackexchange.com/questions/45998/is-energy-the-ability-to-do-work
Mikhail Kats hooding newly minted Dr. Sanket Deshpande at the UW-Madison commencement, May 2026
https://www.insidehighered.com/news/tech-innovation/administrative-tech/2026/05/05/pay-or-leak-hackers-target-big-higher-ed-vendor Article date: May 05
Hantavirus pulmonary syndrome - Symptoms & causes - Mayo Clinic https://share.google/7mfhwuyrvyKhxvBUL
This article has been revised to reflect the following correction: CORRECTION: Oct. 31, 2013 An earlier version of this article misquoted study author Mikhail A. Kats as saying that his team’s findings counteract the law of thermodynamics. In fact, Katslater wrote in an email, while objects typically emit greater amounts of light as their temperature increases, his team demonstrated a structure that exhibits the opposite effect.
DDR/ITG machine
Rack of CDs that mostly hasn't been touched since ... 2004?
City of Madison polling place
NSF proposal status: Recommended
Figure 2. Calculated optical properties of our dielectric-metal-dielectric (DMD) structure, our dual-band selective reflectors (DBSRs), and reference distributed Bragg reflectors (DBRs) with different numbers of layers. (a) Calculated T and R spectra of the DMD structure (Ta2O5 40 nm/Ag 23 nm/Ta2O5 40 nm). (b, c) Calculated (b) T and (c) R spectra of our DBSRs, from 1 to 5 pairs. One pair corresponds to SiO2 108 nm/Ta2O5 112 nm. (d) Calculated R spectra of DBRs, from 1 to 5 pairs. One pair represents SiO2 134 nm/Ta2O5 94 nm. (e, f) Calculated (e) T and (f) R spectra of the integrated photonic structure, where the DMD is placed on top of a DBSR with different numbers of pairs. There is an 80-nm-thick SiO2 intermediate layer as an optical spacer between the DMD and the DBSR.
Figure 1. Optical design and properties of our photonic structure. (a) Schematic of the layered structure. (b) Transmittance (T) and reflectance (R) spectra of an ideal heat-rejection window. The red background is the solar spectrum (AM1.5). (c) Comparison of the solar-spectrum-weighted visible transmittance (Tvis, 400–680 nm) and IR reflectance (RIR, 680–2500 nm) between our photonic structure and previous works. (d) A photo of our photonic structure, fabricated on a 4-inch glass, which shows its high visible transparency. (e, f) Calculated (e) and measured (f) R and T spectra. (g) Calculated (left) and measured (right) angle-dependent R spectra. The input light was assumed to be unpolarized.
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