About

Prof. Lantz is the cognizant scientist for the Advanced LIGO seismic isolation and alignment system, and he leads the research at the Engineering Test Facility for LIGO at Stanford.

Research topics

• Computer Science
• Astronomy
• Physics
• Telecommunications
• Operating system
• Library science
• Astrophysics

Selected publications

• Finding the Maximal Contrast of Two Elliptical Gaussian Mode Beams with Aligned Ellipticities

  ArXiv.org · 2025-12-04

  preprintOpen accessSenior author

  Interferometric contrast is a key factor limiting the sensitivity of precision optical measurements, including the laser interferometers used in gravitational-wave detection. While standard formulas describe the interference of circular Gaussian beams, many real systems use beams with elliptical cross sections, where differing waists and radii of curvature can reduce fringe visibility. This paper derives an analytic expression for the maximum contrast achievable between two aligned elliptical Gaussian beams, written entirely in terms of their geometric and power parameters. We then test the formula using a free-space Michelson interferometer in which all beam parameters are independently measured through beam profiling and nonlinear fitting. In our experiment, the predicted maximum contrast was 0.968 while the experimentally optimized value was 0.950. The small discrepancy is consistent with expected imperfections such as beam rotation, mode mismatch, and non-Gaussian aberrations. This work provides a practical tool for modeling and optimizing elliptical-beam interferometers.

  PublisherOA PDFDOI

• Cosmic Explorer: A Submission to the NSF MPSAC ngGW Subcommittee

  arXiv (Cornell University) · 2023 · 36 citations

  • Physics
  • Astronomy
  • Astrophysics

  Gravitational-wave astronomy has revolutionized humanity's view of the universe, a revolution driven by observations that no other field can make. This white paper describes an observatory that builds on decades of investment by the National Science Foundation and that will drive discovery for decades to come: Cosmic Explorer. Major discoveries in astronomy are driven by three related improvements: better sensitivity, higher precision, and opening new observational windows. Cosmic Explorer promises all three and will deliver an order-of-magnitude greater sensitivity than LIGO. Cosmic Explorer will push the gravitational-wave frontier to almost the edge of the observable universe using technologies that have been proven by LIGO during its development. With the unprecedented sensitivity that only a new facility can deliver, Cosmic Explorer will make discoveries that cannot yet be anticipated, especially since gravitational waves are both synergistic with electromagnetic observations and can reach into regions of the universe that electromagnetic observations cannot explore. With Cosmic Explorer, scientists can use the universe as a laboratory to test the laws of physics and study the nature of matter. Cosmic Explorer allows the United States to continue its leading role in gravitational-wave science and the international network of next-generation observatories. With its extraordinary discovery potential, Cosmic Explorer will deliver revolutionary observations across astronomy, physics, and cosmology including: Black Holes and Neutron Stars Throughout Cosmic Time, Multi-Messenger Astrophysics and Dynamics of Dense Matter, New Probes of Extreme Astrophysics, Fundamental Physics and Precision Cosmology, Dark Matter and the Early Universe.

  PublisherOA PDFDOI

• Open data from the first and second observing runs of Advanced LIGO and Advanced Virgo

  SoftwareX · 2021 · 131 citations

  • Computer Science
  • Computer Science
  • Astronomy
  DOI

• Next Generation Observatories -- Report from the Dawn VI Workshop; October 5-7 2021

  arXiv (Cornell University) · 2021

  • Computer Science
  • Astronomy
  • Library science

  The workshop Dawn VI: Next Generation Observatories took place online over three days, 5-7 October, 2021. More than 200 physicists and astronomers attended to contribute to, and learn from, a discussion of next-generation ground-based gravitational-wave detectors. The program was centered on the next generation of ground-based gravitational-wave observatories and their synergy with the greater landscape of scientific observatories of the 2030s. Cosmic Explorer (CE), a concept developed with US National Science Foundation support, was a particular focus; Einstein Telescope (ET), the European next generation concept, is an important complement and partner in forming a network. The concluding summary of the meeting expressed the sentiment that the observational science accessible to CE and ET, also in combination with data from other non-GW observatories, will stimulate a very broad community of analysts and yield insights which are exciting given the access to GWs from the entire universe. The need, and desire, for closer collaboration between ET and CE was expressed; a three-detector network is optimal for delivering much of the science. The science opportunities afforded by CE and ET are broad and compelling, impacting a wide range of disciplines in physics and high energy astrophysics. There was a consensus that CE is a concept that can deliver the promised science. A strong endorsement of Cosmic Explorer, as described in the CE Horizon Study, is a primary outcome of DAWN VI.

  PublisherOA PDFDOI

• Cryogenic mechanical loss of a single-crystalline GaP coating layer for precision measurement applications

  Physical review. D/Physical review. D. · 2017-02-17 · 8 citations

  articleOpen access

  The first direct observations of gravitational waves have been made by the Advanced LIGO detectors. However, the quest to improve the sensitivities of these detectors remains, and epitaxially grown single-crystal coatings show considerable promise as alternatives to the ion-beam sputtered amorphous mirror coatings typically used in these detectors and other such precision optical measurements. The mechanical loss of a $1\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ thick single-crystalline gallium phosphide (GaP) coating, incorporating a buffer layer region necessary for the growth of high quality epitaxial coatings, has been investigated over a broad range of frequencies and with fine temperature resolution. It is shown that at 20 K the mechanical loss of GaP is a factor of 40 less than an undoped tantala film heat-treated to $600\text{ }\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ and is comparable to the loss of a multilayer GaP/AlGaP coating. This is shown to translate into possible reductions in coating thermal noise of a factor of 2 at 120 K and 5 at 20 K over the current best IBS coatings (alternating stacks of silica and titania-doped tantala). There is also evidence of a thermally activated dissipation process between 50 and 70 K.

  PublisherOA PDFDOI

• Al-doped ZnO amorphous films as conductive layers in ultra-low absorptive optical coatings

  2016-01-01

  articleCorresponding

  Amorphous Al-doped ZnO films useable for charge control on interference mirrors in precision interferometry are described. Absorption of several ppm and Rsh in the GΩ/sq range were obtained in ≤ 500 nm thick films.

  PublisherDOI

• Epitaxial growth of GaP/AlGaP mirrors on Si for low thermal noise optical coatings

  Optical Materials Express · 2015-07-31 · 17 citations

  articleOpen access

  GaP/AlGaP multilayers were grown directly on Si to form a single crystalline mirror with very low mechanical loss. The effects of growth initiation, nucleation layers, and growth variations on antiphase domains and overall film quality were investigated. Using the conditions which yielded smooth nucleation layers and fewer antiphase domains, GaP/AlGaP mirror pairs were grown. These epitaxially-integrated mirrors on Si have potential use in gravitational wave detection, relying on precision interferometric sensing, which requires extremely low mechanical loss in the optical cavities.

  PublisherDOI

Frequent coauthors

• Matteo Barsuglia

  Centre National de la Recherche Scientifique

  4 shared

• R. Bassiri

  University of Glasgow

  4 shared

• R. K. Route

  3 shared

• B. S. Sathyaprakash

  3 shared

• M. M. Fejer

  Stanford University

  3 shared

• V. Martínez

  Université Claude Bernard Lyon 1

  3 shared

• A.S. Markosyan

  University of Glasgow

  3 shared

• D. H. Shoemaker

  Massachusetts Institute of Technology

  3 shared