About

Jason W. Fleischer is a Professor of Electrical and Computer Engineering at Princeton University. His research focuses on nonlinear optics within the broader context of wave physics, emphasizing propagation problems that are universal to wave systems. He leverages the controllability of optical systems to study both fundamental nonlinear physics and advanced photonic applications through a combination of theoretical and experimental approaches. His group has developed the concept of optical hydrodynamics, where the nonlinear propagation of light is described using equations analogous to ideal fluid flow, allowing the experimental demonstration of phenomena such as optical shock waves, instabilities, turbulence, and thermodynamics. Fleischer's work explores the use of wave propagation for dynamical signal processing, including nonlinear wave mixing for energy transfer between modes, which can enhance resolution, field of view, and signal-to-noise ratios. Recently, he has extended computational imaging to include spatial nonlinearity, applying this to microscopy, phase retrieval, and imaging through scattering media, with particular interest in digital holography, noisy imaging, and biomedical optics. His contributions have advanced the understanding of wave physics and opened new avenues for optical physics discovery and applications.

Research topics

• Computer Science
• Physics
• Artificial Intelligence
• Optics
• Quantum mechanics
• Mechanics
• Materials science
• Condensed matter physics

Selected publications

• Snapshot Hyperspectral Imaging via Compressive Sensing and Implicit Neural Representation

  2025-01-01

  articleSenior author

  We propose a snapshot hyperspectral imaging method using randomized aperture codes and implicit neural representations. It shows high performance across a range of hyperspectral datasets, without any external supervision or cross-band information.

  PublisherDOI

• Super-resolution with Fourier measurements

  ArXiv.org · 2025-11-08

  preprintOpen accessSenior author

  Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect alignment with the centroid of the object. Both inhibit the practical application of these methods, as uniform motion and/or relative jitter destroy their assumptions. Here, we show that measuring intensity in the Fourier plane enables super-resolution without any of the issues of image-based methods. We start with the shift-invariance of the Fourier transform and the observation that the two-point position problem ${x_1,x_2}$ in the near field corresponds to the single-point wavenumber problem $k\ =2π/(x_2-x_1)$ in the far field. We consider the full range of mutual coherence and show that for fully coherent sources, the Fourier method saturates the quantum limit, i.e. it gives the best possible measurement. Similar results hold for sub-Rayleigh constellations of $N$ sources, which can act collectively as a spatially averaged metasurface and/or individually as elements of a phased-array antenna. The theory paves the way to merge Fourier optics with super-resolution techniques, enabling experimental devices that are both simpler and more robust than previous designs.

  PublisherOA PDFDOI

• Direct‐Write Printed Contacts to Layered and 2D Materials

  Advanced Electronic Materials · 2025-07-18 · 3 citations

  articleOpen access

  Abstract Advancements in fabrication methods have shaped new computing device technologies. Among these methods, depositing electrical contacts to the channel material is fundamental to device characterization. Novel layered and 2D materials are promising for next‐generation computing electronic channel materials. Direct‐write printing of conductive inks is introduced as a surprisingly effective, significantly faster, and cleaner method to contact different classes of layered materials, including graphene (semi‐metal), MoS 2 (semiconductor), Bi‐2212 (superconductor), and Fe 5 GeTe 2 (metallic ferromagnet). Based on the electrical response, the quality of the printed contacts is comparable to what is achievable with resist‐based lithography techniques. These devices are tested by sweeping gate voltage, temperature, and magnetic field to show that the materials remain pristine post‐processing. This work demonstrates that direct‐write printing is an agile method for prototyping and characterizing the electrical properties of novel layered materials.

  PublisherOA PDFDOI

• Outlier Detection in Large Radiological Datasets using UMAP

  arXiv (Cornell University) · 2024-07-31

  preprintOpen accessSenior author

  The success of machine learning algorithms heavily relies on the quality of samples and the accuracy of their corresponding labels. However, building and maintaining large, high-quality datasets is an enormous task. This is especially true for biomedical data and for meta-sets that are compiled from smaller ones, as variations in image quality, labeling, reports, and archiving can lead to errors, inconsistencies, and repeated samples. Here, we show that the uniform manifold approximation and projection (UMAP) algorithm can find these anomalies essentially by forming independent clusters that are distinct from the main (good) data but similar to other points with the same error type. As a representative example, we apply UMAP to discover outliers in the publicly available ChestX-ray14, CheXpert, and MURA datasets. While the results are archival and retrospective and focus on radiological images, the graph-based methods work for any data type and will prove equally beneficial for curation at the time of dataset creation.

  PublisherOA PDFDOI

• Depth-resolved speckle correlation imaging using the axial memory effect

  Optics Express · 2024-04-26 · 7 citations

  articleOpen accessSenior author

  Speckle correlation imaging (SCI) recovers the angular size of a 2D object hidden behind a scatterer, but it fails to recover its depth. Here, we extend SCI to obtain object depth by capturing speckled images at two detector distances and exploiting the scaling properties of the axial memory effect. This noninvasive method does not require access to the object side of the scatterer, e.g. for pre-calibration or addition of a guide star, and will be useful in any scenario where SCI is applicable, such as biological imaging or seeing through fog.

  PublisherDOI

• Stabilization of permalloy nanoparticles for syringe printable inductors

  Journal of Magnetism and Magnetic Materials · 2024-02-16 · 1 citations

  article
  PublisherDOI

• Fabrication of an Optically Transparent Planar Inverted-F Antenna Using PEDOT-Based Silver Nanowire Clear Ink with Aerosol-Jet Printing Method towards Effective Antennas

  Journal of Manufacturing and Materials Processing · 2024-02-10 · 9 citations

  articleOpen access

  We report the design, fabrication, and experimental characterization of an optically transparent printed planar inverted-F antenna (PIFA) operating at 2.45 GHz using the aerosol jet (AJ) printing method. The proposed antenna was fabricated using a clear conductive ink on glass and Delrin. The antenna exhibits a wide fractional bandwidth (FBW) of 20% centered at 2.45 GHz, with a peak realized gain of −3.6 dBi and transparency of ~80%. The proposed fabrication method provides a cost-effective and scalable solution for manufacturing transparent antennas with potential applications in wireless communication, sensing, and wearable devices operating at mmWave frequencies higher than 30 GHz.

  PublisherOA PDFDOI

• Magnetic Ferrite Nanoparticle Inks for Syringe Printable Inductors

  ACS Applied Electronic Materials · 2024-05-13 · 2 citations

  article

  Additive manufacturing has the potential to simplify fabrication processes by using a single apparatus that exchanges printable material at the print head to create complex shapes. Circuit components can be made of various materials such as magnetic materials, which are specifically used for many applications, including inductors. Few syringe printable magnetic inks have been explored, and even fewer to create a final product with high magnetic content compared to polymer content (>90 vol %). In this study, syringe printable, colloidal magnetic inks are made using both iron oxide and MnZn doped ferrite nanoparticles by stabilizing them with poly(acrylic acid) (PAA) and adding a free polymer poly(ethylene oxide) (PEO) of various molecular weights and glycerol to control ink viscosity and evaporation rates. Printability is further explained using complex rheology. MnZn doped ferrite inks are printed into toroids and sintered at 1400 °C to increase magnetic permeability. A sintered toroid is constructed into an inductor device and characterized using a Vector Network Analyzer (VNA), which exhibits an inductance of 4.26 μH at 8.5 MHz. This study lays out a template for ferrite inks with the potential to be fabricated into useful passive electronic devices.

  PublisherDOI

• Outlier Detection in Large Radiological Datasets Using UMAP

  Lecture notes in computer science · 2024-10-10 · 1 citations

  book-chapterSenior author
  PublisherDOI

• Temperature-Humidity-Bias Testing and Life Prediction Modeling for Electrochemical Migration in Aerosol-Jet Printed Circuits

  Journal of Electronic Packaging · 2023-09-29 · 2 citations

  article

  Abstract Aerosol-Jet Printing (AJP) technology, applied to the manufacturing of printed hybrid electronics (PHE) devices, has the capability to fabricate highly complex structures with resolution in the tens-of-microns scale, creating new possibilities for the fabrication of electronic devices and assemblies. The widespread use of AJP in fabricating PHE and package-level electronics necessitates a thorough assessment of not only the performance of AJP printed electronics but also their reliability under different kinds of life-cycle operational and environmental stresses. One important hindrance to the reliability and long-term performance of such AJP electronics is electrochemical migration (ECM). ECM is an important failure mechanism in electronics under temperature and humidity conditions because it can lead to conductive dendritic growth, which can cause dielectric breakdown, leakage current, and unexpected short circuits. In this paper, the ECM propensity in conductive traces printed with AJP process, using silver-nanoparticle (AgNP) based inks, was experimentally studied using temperature-humidity-bias (THB) testing of printed test coupons. Conductive dendritic growth with complex morphologies was observed under different levels of temperature, humidity, and electric bias in the THB experiments. Weibull statistics are used to quantify the failure data, along with the corresponding confidence bounds to capture the uncertainty of the Weibull distribution. A nonmonotonic relationship between time-to-failure and electric field strength was noticed. An empirical acceleration model for ECM is proposed, by combining the classical Peck's model with a quadratic polynomial dependence on electric field strength. This model provides good estimate of acceleration factors for use conditions where the temperature, humidity, and electrical field are within the tested range, but should be extrapolated with care beyond the tested range.

  PublisherDOI

Recent grants

• Nonlinear dynamics of partially-coherent waves: experimental and theoretical studies in statistical light

  NSF · $344k · 2006–2010

Frequent coauthors

• Mordechai Segev

  72 shared

• Dmitry V. Dylov

  36 shared

• Christopher Barsi

  35 shared

• Shu Jia

  Georgia Institute of Technology

  32 shared

• Oren Cohen

  Technion – Israel Institute of Technology

  32 shared

• Hrvoje Buljan

  University of Zagreb

  29 shared

• Wenjie Wan

  Shanghai Jiao Tong University

  28 shared

• Guy Bartal

  28 shared

Labs

• Fleischer GroupPI

  Imaging Physics Group

Awards & honors

• Fellow of Optical Society of America (2012)
• Department of Energy Plasma Physics Junior Faculty Award (20…
• Emerson Electric Company Lawrence Keys '51 Faculty Advanceme…
• Lady Davis Postdoctoral fellowship, Israel (2001-2004)
• University of California Regents Fellowship (1994-1999)