About

Javier E. Garay is a Professor of Mechanical and Aerospace Engineering and the Associate Dean for Research at the Jacobs School of Engineering at UC San Diego. He received his B.S. in Mechanical Engineering in 1999, M.S. in Materials Science and Engineering in 2002, and Ph.D. in Materials Science and Engineering in 2004, all from the University of California, Davis. Prior to joining UC San Diego in 2015, he was a professor at UC Riverside, where he also served as Chair of the Materials Science & Engineering Program from 2012 to 2015. Professor Garay is the principal investigator of the Advanced Material Processing and Synthesis (AMPS) Lab, which focuses on advanced material processing and synthesis with an emphasis on designing the micro/nanostructure of bulk materials for property optimization. His research includes understanding the role of nano-/micro-structural features on light, heat, and magnetism, as well as developing materials for next-generation optical, magnetic, and energy storage devices. The AMPS Lab has capabilities in property measurements and device design, enabling seamless integration between material design and performance evaluation.

Research topics

• Genetics
• Biology
• Computational biology
• Organic chemistry
• Condensed matter physics
• Physics
• Thermodynamics
• Chemistry
• Materials science
• Chemical physics

Selected publications

• Ultrafast, high-intensity laser material interaction in polycrystalline alumina transparent ceramics

  Acta Materialia · 2025-08-18 · 2 citations

  articleSenior authorCorresponding
  PublisherDOI

• Ultrafast, High-Intensity Laser Material Interaction in Polycrystalline Alumina Transparent Ceramics

  SSRN Electronic Journal · 2025-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Synthesis of YSZ nanoparticles using laser ablation of solids in liquids

  Journal of Alloys and Compounds · 2025-08-01

  article
  PublisherDOI

• Synthesis of Ysz Nanoparticles: Stoichiometric Retention, Phase Transition, and Doping-Dependent Properties

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• Sensitivity analysis of the geometrical simplification of an intercity train entering a tunnel

  Journal of Wind Engineering and Industrial Aerodynamics · 2025-08-03

  articleOpen accessSenior author

  This paper presents a study of several levels of simplification of the geometrical features of the locomotive unit, in good agreement with these proposed in the European standards, in order to study the sensitivity of the compression wave profile and the pressure gradient measured at the tunnel entrance. The European standards permits in computational fluid dynamic studies the simplification of the bogies while other aerodynamically significant features shall be modeled in detail. Here the snowplow, the coupler elements and the bogies are studied to determine the influence of each element on the compression wave and the maximum pressure gradient of a intercity train entering into a tunnel. It is observed that the coupler introduces a delay in the pressure rise measured at the tunnel walls when the train nose is entering. The snowplow introduces a flow detachment that increases the effective cross-sectional area of the train, and so increases the pressure rise. The removal of the bogies clearly modifies the train head cross-sectional area, so its substitution by a dummy box provokes an increase in the pressure rise that approximates the maximum pressure gradient to that obtained from the full-detailed case.

  PublisherDOI

• Laser processing approaches for functional nano- and microstructures with photonic applications

  2025-09-16 · 1 citations

  article

  Photonic materials with sub-wavelength features have enabled unique light-matter interactions; however, fabrication methods face challenges in achieving high-resolution features and tunable structures at scale. In this work, laser-processing of photonic materials is studied. First, multilayered gratings are fabricated using two-photon absorption lithography for polarization-sensitive structural colors. By varying the grating design and light polarization conditions, the transmitted structural color response is analyzed. Next, we investigate the laser focusing beyond Abbe’s diffraction limit using ultrasmooth plasmonic pyramidal arrays. The electric field enhancement due to nanoscale curvature at the apex is characterized, and pyramidal structures of different metals are integrated into a high-precision substrate patterning setup. Overall, this work showcases high-resolution feature size and structural control in laser-based techniques, offering insights into novel micro- and nanofabrication techniques.

  PublisherDOI

• Shock measurements of alternative tamper materials YAG and GGG

  Optics Letters · 2025-03-20 · 2 citations

  article

  Tamper materials allow for pressure maximization in a shock experiment up until their saturation limit. The Fabbro model provides the basis for the prediction for pressure enhancement from tamper materials. In this paper, we report the performance of two novel, to the best of our knowledge, tamper materials (yttrium aluminum garnet (YAG) and gadolinium gallium garnet (GGG)) using the Fabbro model and experimental data. The pressure enhancement using a laser-driven shock in the 2 GPa range and the saturation curve as these novel tampers compare to traditional tampers is explored. The unexpectedly low saturation points of YAG and GGG are discussed because of variable surface quality of commercially available samples. Overall, this study’s findings suggest that YAG and GGG show promise as alternative tampers, provided that anticipated enhancements in surface quality are achieved. At fluences of 5 J/cm 2 , a strong dependence of maximum pressure on the total acoustic impedance of the sample is not observed, and tamper selection becomes negligible.

  PublisherDOI

• Acoustically Transparent Alumina-based Cranial Implants Enhance Ultrasound Transmission Through a Combined Mechano-Acoustic Resonant Effect

  arXiv (Cornell University) · 2024-06-19

  preprintOpen accessSenior author

  Therapeutic ultrasound for brain stimulation has increased in the last years. This energy has shown promising results for treating Alzheimers disease, Parkinsons disease, and traumatic brain injury, among other conditions. However, the application of ultrasound in the brain should trespass a natural but highly attenuating and distorting barrier, the cranium. Implantable ceramic materials can be used to replace part of the cranium as an alternate method to enhance ultrasound transmission. In this work, it is presented the acoustic characterization of alumina ceramic disks that can be employed as cranial implants for acoustic windows-to-the-brain. Alumina samples were prepared using current-activated pressure-assisted densification and were acoustically characterized. Acoustic impedance and attenuation of the samples were determined for different porosities. Additionally, measured and modeled acoustic fields are presented and analyzed in terms of the total ultrasound transmitted through the ceramics. Results indicate a resonant behavior in the alumina disks when the thickness corresponds to a half-wavelength of ultrasound; this resonance permits a total of 95.4% of ultrasound transmission; for thicknesses out of the resonant zone, transmission is 53.0%. Alumina proves to be an excellent medium for ultrasound transmission that, in conjunction with its mechanical and optical properties, can be useful for cranium replacement in mixed opto-acoustic applications.

  PublisherOA PDFDOI

• Laser material interaction of undoped and doped silicon

  2024-04-10

  articleSenior author

  This research looks to enhance our understanding of the laser-material interaction within silicon, considering variations in free carrier density. Silicon exhibits distinct optical behaviors, ranging from transparency to non-transparency, contingent on its doping concentration, particularly at a 1064 nm wavelength. Our experimental investigation delves into the quantitative assessment of damage size and the qualitative characterization of damage morphology induced by singlepulse 1064 nm laser irradiation. In this experiment, we vary laser intensities and focal depths to show their influence on the damage features of single crystal silicon with varying doping concentrations. The damage size and qualitative characteristics can be used to better understand the mechanisms responsible for the laser damage. Additionally, we can see when the damaged silicon is exhibiting pure melting or a form of ordered damage at higher intensities. The findings of this study give insight into the optimization of laser processing techniques that require precise control over material ablation, and phase change as cutting and material joining. Furthermore, the insights garnered from this work contribute to a broader understanding of the interplay between laser parameters and material properties. This study represents a move towards unlocking the potential of laser-matter interactions in shaping the future of silicon advanced manufacturing technologies.

  PublisherDOI

• Laser pulse-length dependent ablation and shock generation in silicon at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>5</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mn>10</mml:mn><mml:mn>14</mml:mn></mml:msup></mml:mrow></mml:math> W/<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mi mathvariant="normal">cm</mml:mi><mml:mn>2</mml:mn></mml:msup></mml:math> intensities

  Physical Review Research · 2024-07-11 · 1 citations

  articleOpen access

  The effect of laser pulse duration on energy coupling into a planar silicon target is investigated in experiments at the OMEGA-EP facility by varying the laser pulse length <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mi>τ</a:mi></a:math>—spanning 3 orders of magnitude from 100 ps to 10 ns—while maintaining a constant peak laser intensity, <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mrow><b:msub><b:mi>I</b:mi><b:mn>0</b:mn></b:msub><b:mo>=</b:mo><b:mn>5</b:mn><b:mo>×</b:mo><b:msup><b:mn>10</b:mn><b:mn>14</b:mn></b:msup></b:mrow></b:math> W/<c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:msup><c:mi mathvariant="normal">cm</c:mi><c:mn>2</c:mn></c:msup></c:math>. In theoretical models, the ablation pressure primarily scales for a given material with laser intensity and wavelength, which are all fixed variables here, allowing us to explore the specific role of laser pulse duration. Two-dimensional radiation-hydrodynamics simulations benchmarked with optical probing of the expanding plasma show that the pulse duration is critical for the ablation pressure to reach a steady state. Moreover, the pulse duration impacts shock decay and multiple wave effects, which strongly dictate the evolving shock profile that propagates within the laser-shocked target as ultimately measured by rear-surface diagnostics. The shock velocities inferred from the theoretical model, after considering shock decay, impedance matching, and shock Hugoniot, are found to be in good agreement with velocimetry measurements. However, discrepancies are observed with simulations for the shorter (0.1 ns) and longer (10 ns) pulse durations, which are respectively attributed to unaccounted contributions of kinetic absorption mechanisms and instabilities in simulations. Published by the American Physical Society 2024

  PublisherOA PDFDOI

Recent grants

• CAREER: Optoelectronic Nanocomposites: Controlling the Properties of Bulk Ceramic Heterostructures using External Electric Fields.

  NSF · $435k · 2010–2015

• Rheology of Nanocrystalline Materials: Clarifying the Sliding Mechanism of Earthquakes

  NSF · $270k · 2014–2018

• Rheology of Nanocrystalline Materials: Clarifying the Sliding Mechanism of Earthquakes

  NSF · $57k · 2017–2019

Frequent coauthors

• Yasuhiro Kodera

  Nagoya University

  72 shared

• Elías H. Penilla

  Jacobs (United States)

  47 shared

• Yasuhiro Kodera

  Materials Processing (United States)

  34 shared

• A. D. Volodchenkov

  University of California, San Diego

  23 shared

• Zuhair A. Munir

  22 shared

• Pathikumar Sellappan

  22 shared

• Corey L. Hardin

  University of California, San Diego

  20 shared

• Umberto Anselmi‐Tamburini

  University of Pavia

  18 shared

Education

• B.S.

  University of California, Davis

  1999

• M.S.

  University of California, Davis

  2002

• Ph.D.

  University of California, Davis

  2004

Awards & honors

• Army Research Office (ARO-YIP) (2005)
• Air Force Office for Scientific Research (AFOSR-YIP) (2009)
• Faculty Early Career Development (CAREER) award from the Nat…