About

David Bishop, PhD, is a professor at Boston University College of Engineering with primary appointments in Electrical and Computer Engineering, Physics, Materials Science and Engineering, Mechanical Engineering, and Biomedical Engineering. He is the head of the Division of Materials Science & Engineering and the director of the CELL-MET Engineering Research Center. His educational background includes a PhD from Cornell University obtained in 1978. His areas of interest encompass cardiac tissue engineering, SAXS studies of cardiac tissues, MEMS and NEMS, Casimir effect, superconductivity and superfluidity, feedforward control theory algorithms, nanomanufacturing, and nanotechnology. Dr. Bishop has received numerous honors and awards, including fellowships with the National Academy of Inventors, the American Physical Society, and the US National Academy of Engineering. He is also a recipient of the George E. Pake Prize, the Nano50 Innovator Award, and fellowships and awards from Bell Labs. In addition to his research, Dr. Bishop holds leadership roles as the head of the Division of Materials Science & Engineering and as director of the CELL-MET Engineering Research Center. His departmental affiliations include Biomedical Engineering, Electrical & Computer Engineering, Materials Science & Engineering, and Mechanical Engineering, along with involvement in the Photonics Center and other departmental and affiliated faculties.

Research topics

• Physics
• Computer Science
• Epistemology
• Philosophy
• Theoretical physics
• Acoustics
• Quantum electrodynamics
• Classical mechanics
• Optics
• Materials science
• Optoelectronics

Selected publications

• Zeptonewton and attotesla per centimeter metrology with coupled oscillators

  Chaos An Interdisciplinary Journal of Nonlinear Science · 2024-07-01 · 2 citations

  articleSenior author

  We present the coupled oscillator: A new mechanism for signal amplification with widespread application in metrology. We introduce the mechanical theory of this framework and support it by way of simulations. We present a particular implementation of coupled oscillators: A microelectromechanical system (MEMS) that uses one large (∼100mm) N52 magnet coupled magnetically to a small (∼0.25mm), oscillating N52 magnet, providing a force resolution of 200zN measured over 1s in a noiseless environment. We show that the same system is able to resolve magnetic gradients of 130aT/cm at a single point (within 500μm). This technology, therefore, has the potential to revolutionize force and magnetic gradient sensing, including high-impact areas such cardiac and brain imaging.

  PublisherDOI

• Contents list

  Faraday Discussions · 2024-01-01

  articleOpen access

  Permissions Request permissions Contents list Faraday Discuss., 2024, 248, 3 DOI: 10.1039/D4FD90002B This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given. Read more about how to correctly acknowledge RSC content.

  PublisherOA PDFDOI

• Low-loss liquid metal interconnects for superconducting quantum circuits

  Applied Physics Letters · 2024-06-24 · 2 citations

  preprintOpen accessSenior author

  Building a modular architecture with superconducting quantum computing chips is one of the means to achieve qubit scalability, allowing the screening, selection, replacement, and integration of individual qubit modules into large quantum systems. However, the nondestructive replacement of modules within a compact architecture remains a challenge. Liquid metals, specifically gallium alloys, can be alternatives to solid-state galvanic interconnects. This is motivated by their self-healing, self-aligning, and other desirable fluidic properties, potentially enabling the nondestructive replacement of modules at room temperatures, even after operating the entire system at millikelvin regimes. In this study, we present coplanar waveguide resonators (CPWRs) interconnected by gallium alloy droplets, achieving high internal quality factors up to nearly one million and demonstrating performance on par with the continuous solid-state CPWRs. Leveraging the desirable fluidic properties of gallium alloys at room temperature and their compact design, we envision a modular quantum system enabled by liquid metals.

  PublisherOA PDFDOI

• Seeking the Casimir energy

  International Journal of Modern Physics A · 2024-12-27

  articleSenior author

  Since its first description in 1948, the Casimir effect has been studied extensively. Standard arguments for its existence hinge on the elimination of certain modes of the electromagnetic field because of the boundary conditions in the Casimir cavity. As such, it has been suggested that the ground state energy of the vacuum within the cavity may be reduced compared to the value outside. Could this have an effect on physical phenomena within the cavity? We study this Casimir energy and probe whether the critical temperature [Formula: see text] of a superconductor is altered when it is placed in the cavity. We do not detect any change in [Formula: see text] larger than 12[Formula: see text][Formula: see text]K, but theoretically expect a change on the order of 0.025[Formula: see text][Formula: see text]K, roughly 1000 times lower than our achieved sensitivity.

  PublisherDOI

• Zeptonewton and Attotesla per Centimeter Metrology With Coupled Oscillators

  arXiv (Cornell University) · 2024-02-22

  preprintOpen accessSenior author

  We present the coupled oscillator: a new mechanism for signal amplification with widespread application in metrology. We introduce the mechanical theory of this framework, and support it by way of simulations. We present a particular implementation of coupled oscillators: a microelectromechanical system (MEMS) that uses one large (~100mm) N52 magnet coupled magnetically to a small (~0.25mm), oscillating N52 magnet, providing a force resolution of 200zN measured over 1s in a noiseless environment. We show that the same system is able to resolve magnetic gradients of 130aT/cm at a single point (within 500um). This technology therefore has the potential to revolutionize force and magnetic gradient sensing, including high-impact areas such cardiac and brain imaging.

  PublisherOA PDFDOI

• Seeking the Casimir Energy

  arXiv (Cornell University) · 2024-12-13

  preprintOpen accessSenior author

  Since its first description in 1948, the Casimir effect has been studied\nextensively. Standard arguments for its existence hinge on the elimination of\ncertain modes of the electromagnetic field because of the boundary conditions\nin the Casimir cavity. As such, it has been suggested that the ground state\nenergy of the vacuum within the cavity may be reduced compared to the value\noutside. Could this have an effect on physical phenomena within the cavity? We\nstudy this Casimir energy and probe whether the critical temperature $T_c$ of a\nsuperconductor is altered when it is placed in the cavity. We do not detect any\nchange in $T_c$ larger than 12 microKelvin, but theoretically expect a change\non the order of 0.025 microKelvin, roughly 1000 times lower than our achieved\nsensitivity.\n

  PublisherOA PDFDOI

• Structural maturation of myofilaments in engineered 3D cardiac microtissues characterized using small angle x-ray scattering

  Physical Biology · 2024-03-07 · 1 citations

  articleOpen accessSenior author

  Understanding the structural and functional development of human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs) is essential to engineering cardiac tissue that enables pharmaceutical testing, modeling diseases, and designing therapies. Here we use a method not commonly applied to biological materials, small angle x-ray scattering, to characterize the structural development of hiPSC-CMs within three-dimensional engineered tissues during their preliminary stages of maturation. An x-ray scattering experimental method enables the reliable characterization of the cardiomyocyte myofilament spacing with maturation time. The myofilament lattice spacing monotonically decreases as the tissue matures from its initial post-seeding state over the span of 10 days. Visualization of the spacing at a grid of positions in the tissue provides an approach to characterizing the maturation and organization of cardiomyocyte myofilaments and has the potential to help elucidate mechanisms of pathophysiology, and disease progression, thereby stimulating new biological hypotheses in stem cell engineering.

  PublisherOA PDFDOI

• Tuning the pH Response of Monolayer Hexagonal Boron Nitride/Graphene Field-Effect Transistors

  Research Square · 2023-02-23

  preprintOpen accessSenior author

  Abstract Scaling the fabrication of 2D devices for pH sensing will have implications in materials and life sciences. Monolayer hexagonal boron nitride has recently reached commercial wafer-scale transferability on monolayer graphene and is hypothesized to preserve graphene quality, reducing device-to-device variation, while simultaneously screening charge density at the liquid-solid interface resulting in attenuation of pH sensitivity of the graphene transducer. The pH-dependencies of field-effect transistors derived from monolayer hexagonal boron nitride/graphene were compared to monolayer graphene on four-inch SiO2/p-type Si wafers. Photoresistless fabrication of the two-dimensional devices relied on shadow masking for metallization, and the sensing areas were defined using microcentrifuge tube masking and reactive ion etching to produce quasi-pure sensing areas. Microcentrifuge tubes sealed the devices and were opened for experimentation where the liquid-gated Dirac voltages were studied as a function of pH in 10 mM phosphate solutions. The sensitivity of the shift in the Dirac voltage versus pH of hexagonal boron nitride/graphene devices (-40 mV/pH) was smaller than bare graphene (-47 mV/pH) with greatest attenuation in the acidic regime. Moreover, triplicating this experiment revealed smaller standard deviations for the hexagonal boron nitride/graphene transistors. Then, electron beam and atomic layer deposition of AlxOy nanofilms were employed before encapsulation to study the tunability of the pH response of hexagonal boron nitride/graphene and revealed thickness-dependent enhancement, with the greatest sensitivity on 8.6 nm AlxOy/hBN/graphene/SiO2 (-100 mV/pH). Then, reversion of the pH response upon dissolving the AlxOy was characterized. In this work, nanoscale dielectrics enabled tuning of the electrical response of graphene-based pH sensors.

  PublisherOA PDFDOI

• Modal engineering of electromagnetic circuits to achieve rapid settling times

  Review of Scientific Instruments · 2023-01-01 · 1 citations

  articleOpen accessSenior author

  Inductive circuits and devices are ubiquitous and important design elements in many applications, such as magnetic drives, galvanometers, magnetic scanners, applying direct current (DC) magnetic fields to systems, radio frequency coils in nuclear magnetic resonance (NMR) systems, and a vast array of other applications. They are widely used to generate both DC and alternating current (AC) magnetic fields. Many of these applications require a rapid step and settling time, turning the DC or AC magnetic field on and off quickly. The inductive response normally makes this a challenging thing to do. In this article, we discuss open loop control algorithms for achieving rapid step and settling times in four general categories of applications: DC and AC systems where the system is either under- or over-damped. Each of these four categories requires a different algorithm, which we describe here. We show the operation of these drive methods using Simulink and Simscape modeling tools, analytical solutions to the underlying differential equations, and experimental results using an inductive magnetic coil and a Hall sensor. Finally, we demonstrate the application of these techniques to significantly reduce ringing in a standard NMR circuit. We intend this article to be practical, with useful, easy-to-apply algorithms and helpful tuning tricks.

  PublisherDOI

• Structural maturation of myofilaments in engineered 3D cardiac microtissues characterized using small angle X-ray scattering

  Research Square · 2023-06-22

  preprintOpen access
  PublisherOA PDFDOI

Recent grants

• Detecting the Casimir Energy

  NSF · $370k · 2017–2021

• Building a MEMS-based Fab-on-a-Chip as a Technique for Nanomanufacturing

  NSF · $394k · 2014–2018

• Nanosystems Engineering Research Center for Directed Multiscale Assembly of Cellular Metamaterials with Nanoscale Precision: CELL-MET

  NSF · $39.1M · 2017–2027

Frequent coauthors

• Matthias Imboden

  79 shared

• Lawrence Barrett

  Boston University

  72 shared

• P. L. Gammel

  61 shared

• David Campbell

  56 shared

• Josh Javor

  Boston University

  42 shared

• Alexander Stange

  33 shared

• Pablo G. del Corro

  Laboratoire de l'Intégration du Matériau au Système

  32 shared

• F. de la Cruz

  29 shared

Education

• Ph.D., Electrical Engineering

  University of X

  2005

• M.S., Electrical Engineering

  University of Y

  2002

• B.S., Electrical Engineering

  University of Z

  1999

Awards & honors

• Fellow, National Academy of Inventors
• Member, US National Academy of Engineering
• Fellow, American Physical Society
• George E. Pake Prize, American Physical Society
• Nano50 Innovator Award