Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review Letters

Interaction-Free Measurement with Electrons

Amy E. Turner, Cameron Johnson, Pieter Kruit, Benjamin J. McMorran

Published Sep 7, 2021• 53 citations
Publisher

Abstract

Here, we experimentally demonstrate interaction-free measurements with electrons using a novel electron Mach-Zehnder interferometer. The flexible two-grating electron interferometer is constructed in a conventional transmission electron microscope and achieves high contrast in discrete output detectors, tunable alignment with independently movable beam splitters, and scanning capabilities for imaging. With this path-separated electron interferometer, which closely matches theoretical expectations, we demonstrate electron interaction-free measurements with an efficiency of 14±1%. Implementing this quantum protocol in electron imaging opens a path toward interaction-free electron microscopy.

DOI
10.1103/physrevlett.127.110401

Related papers

Reduced damage in electron microscopy by using interaction-free measurement and conditional reillumination

Akshay Agarwal, Karl K. Berggren, Yuri J. van Staaden +1 more

Interaction-free measurement (IFM) has been proposed as a means of high-resolution, low-damage imaging of radiation-sensitive samples, such as biomolecules and proteins. The basic setup for IFM is a Mach-Zehnder interferometer, and recent progress in nanofabricated electron-diffraction gratings has made it possible to incorporate a Mach-Zehnder interferometer in a transmission electron microscope (TEM). Therefore, the limits of performance of IFM with such an interferometer and a shot-noise limited electron source (such as that in a TEM) are of interest. In this paper, we compare the error probability and sample damage for ideal IFM and classical imaging schemes, through theoretical analysis and numerical simulation. We consider a sample that is either completely transparent or completely opaque at each pixel. In our analysis, we also evaluate the impact of an additional detector for scattered electrons. Inclusion of the scattering detector results in reduction of error by up to an order of magnitude, for both IFM and classical schemes. We also investigate a sample reillumination scheme based on updating priors after each round of illumination and find that this scheme further reduces error. Implementation of these methods is likely achievable with existing instrumentation and would result in improved resolution in low-dose electron microscopy.

arXiv:1901.09702•Physical Review A•Jun 5, 2019•12 citations

Designs for a quantum electron microscope

P. Kruit, Richard G. Hobbs, Chung-Soo Kim +11 more

One of the astounding consequences of quantum mechanics is that it allows the detection of a target using an incident probe, with only a low probability of interaction of the probe and the target. This 'quantum weirdness' could be applied in the field of electron microscopy to generate images of beam-sensitive specimens with substantially reduced damage to the specimen. A reduction of beam-induced damage to specimens is especially of great importance if it can enable imaging of biological specimens with atomic resolution. Following a recent suggestion that interaction-free measurements are possible with electrons, we now analyze the difficulties of actually building an atomic resolution interaction-free electron microscope, or "quantum electron microscope". A quantum electron microscope would require a number of unique components not found in conventional transmission electron microscopes. These components include a coherent electron beam-splitter or two-state-coupler, and a resonator structure to allow each electron to interrogate the specimen multiple times, thus supporting high success probabilities for interaction-free detection of the specimen. Different system designs are presented here, which are based on four different choices of two-state-couplers: a thin crystal, a grating mirror, a standing light wave and an electro-dynamical pseudopotential. Challenges for the detailed electron optical design are identified as future directions for development. While it is concluded that it should be possible to build an atomic resolution quantum electron microscope, we have also identified a number of hurdles to the development of such a microscope and further theoretical investigations that will be required to enable a complete interpretation of the images produced by such a microscope.

arXiv:1510.05946•Ultramicroscopy•Mar 9, 2016•161 citations

Electron matter optics and an electron Mach -Zehnder interferometer

Glen Gronniger

The diffraction of electrons by natural crystal structures was first observed in 1927. Before the start of this work, it was not clear whether or not the high quality gratings currently available could be used for electron diffraction due to image charge and other electron grating interactions. We observe for the first time electron diffraction from man made diffraction gratings of 100 nm periodicity. The high quality of diffraction and the ability to "pick" the periodicity allowed us to construct the first Mach-Zehnder electron interferometer using these gratings. Multiple approaches, including a prototype of our current interferometer and the combination of a grating with an electron bi-prism, were unsuccessful. Many stabilization issues must be overcome to observe electron interference fringes in the interferometer. Many experimental design ideas were used to reach proper stabilization requirements. The final interferometer design constructed was the only interferometer to obtain electron interference fringes. The theoretical model used to analyze the data is based on the path integral formalism. This calculates the amplitude associated with all classical paths through the experimental device. The sum of all amplitudes, the path integral, yields the resulting probability at the detection screen. We obtain good fits between our path integral calculations and experimental data. Alternate explanations of our data, such as the possibilities of Talbot Lau and classical Moiré interferometers are ruled out in favor of the Mach-Zehnder explanation. This type of interferometer could be used for future experiments. An experiment for which the fundamental quantum mechanical experiment has never been done; observing the dispersion-less nature of the Aharonov-Bohm Effect, may lend itself to the characteristics of this type of interferometer. Preliminary calculations have been performed to investigate the feasibility of using the grating technology to perform the required experiment.

•Jan 1, 2006•0 citations

Efficient two-port electron beam splitter via a quantum interaction-free measurement

Yujia Yang, Chung-Soo Kim, Richard G. Hobbs +2 more

Semitransparent mirrors are standard elements in light optics for splitting light beams or creating two versions of the same image. Such mirrors do not exist in electron optics, although they could be beneficial in existing techniques such as electron interferometry and holography and could enable alternative electron imaging and spectroscopy techniques. We propose a design for an electron beam splitter using the concept of quantum interaction-free measurement (IFM). The design combines an electron resonator with a weak phase grating. Fast switching gates allow electrons to enter and exit the resonator. While in the resonator, the phase grating transfers intensity from the direct beam into one of the weakly diffracted beams at each pass. To make the beam splitter an efficient two-port splitter, the intensity in all other diffracted beams is blocked by an aperture. The IFM principle minimizes the loss of total intensity by this aperture. We use a scattering matrix method to analyze the performance of the beam splitter, including the effects of inelastic scattering in the phase grating. This design can be generalized to beam splitters for not only electrons, but also photons, neutrons, atoms, and other quantum mechanical systems.

arXiv:1808.03363•Physical Review A•Oct 17, 2018•11 citations

Multi-pass transmission electron microscopy

Thomas Juffmann, Stewart A. Koppell, Brannon B. Klopfer +3 more

Feynman once asked physicists to build better electron microscopes to be able to watch biology at work. While electron microscopes can now provide atomic resolution, electron beam induced specimen damage precludes high resolution imaging of sensitive materials, such as single proteins or polymers. Here, we use simulations to show that an electron microscope based on a multi-pass measurement protocol enables imaging of single proteins, without averaging structures over multiple images. While we demonstrate the method for particular imaging targets, the approach is broadly applicable and is expected to improve resolution and sensitivity for a range of electron microscopy imaging modalities, including, for example, scanning and spectroscopic techniques. The approach implements a quantum mechanically optimal strategy which under idealized conditions can be considered interaction-free.

Scientific Reports•May 4, 2017•58 citations

Quantum interaction-free measurement

Zhi-chuan Dong, Peng Zhuang

"Interaction-free measurements" (IFM) originate from the latest quantum interferometric technologies. The latest research of quantum optics demonstrates, by using the complementary wavelike and particlelike natures of photons, it is possible to make interaction-free measurements by which the presence of an object can be determined with no photons being absorbed. The paper introduces the concept of "Interaction-free Measurement" (IFM), the original Elitzur-Vaidman scheme, the "High Efficiency Interaction-free Measurement", the application of quantum Zeno effect and the improved scheme proposed by Kwiat et al. The EV scheme is implemented in a Mach-Zehnder interferometer. Theoretically this paper also draws a conclusion in IFM feasibility by analyzing the wave functions of photon at various locations in the interferometer.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Feb 13, 2006•0 citations
Here, we experimentally demonstrate interaction-free measurements with electrons using a novel electron Mach-Zehnder interferometer. The flexible two-grating electron interferometer is constructed in a conventional transmission electron microscope and achieves high contrast in discrete output detectors, tunable alignment with independently movable beam splitters, and scanning capabilities for imaging. With this path-separated electron interferometer, which closely matches theoretical expectations, we demonstrate electron interaction-free measurements with an efficiency of 14±1%. Implementing this quantum protocol in electron imaging opens a path toward interaction-free electron microscopy.
Interaction-free measurement (IFM) has been proposed as a means of high-resolution, low-damage imaging of radiation-sensitive samples, such as biomolecules and proteins. The basic setup for IFM is a Mach-Zehnder interferometer, and recent progress in nanofabricated electron-diffraction gratings has made it possible to incorporate a Mach-Zehnder interferometer in a transmission electron microscope (TEM). Therefore, the limits of performance of IFM with such an interferometer and a shot-noise limited electron source (such as that in a TEM) are of interest. In this paper, we compare the error probability and sample damage for ideal IFM and classical imaging schemes, through theoretical analysis and numerical simulation. We consider a sample that is either completely transparent or completely opaque at each pixel. In our analysis, we also evaluate the impact of an additional detector for scattered electrons. Inclusion of the scattering detector results in reduction of error by up to an order of magnitude, for both IFM and classical schemes. We also investigate a sample reillumination scheme based on updating priors after each round of illumination and find that this scheme further reduces error. Implementation of these methods is likely achievable with existing instrumentation and would result in improved resolution in low-dose electron microscopy.
One of the astounding consequences of quantum mechanics is that it allows the detection of a target using an incident probe, with only a low probability of interaction of the probe and the target. This 'quantum weirdness' could be applied in the field of electron microscopy to generate images of beam-sensitive specimens with substantially reduced damage to the specimen. A reduction of beam-induced damage to specimens is especially of great importance if it can enable imaging of biological specimens with atomic resolution. Following a recent suggestion that interaction-free measurements are possible with electrons, we now analyze the difficulties of actually building an atomic resolution interaction-free electron microscope, or "quantum electron microscope". A quantum electron microscope would require a number of unique components not found in conventional transmission electron microscopes. These components include a coherent electron beam-splitter or two-state-coupler, and a resonator structure to allow each electron to interrogate the specimen multiple times, thus supporting high success probabilities for interaction-free detection of the specimen. Different system designs are presented here, which are based on four different choices of two-state-couplers: a thin crystal, a grating mirror, a standing light wave and an electro-dynamical pseudopotential. Challenges for the detailed electron optical design are identified as future directions for development. While it is concluded that it should be possible to build an atomic resolution quantum electron microscope, we have also identified a number of hurdles to the development of such a microscope and further theoretical investigations that will be required to enable a complete interpretation of the images produced by such a microscope.
The diffraction of electrons by natural crystal structures was first observed in 1927. Before the start of this work, it was not clear whether or not the high quality gratings currently available could be used for electron diffraction due to image charge and other electron grating interactions. We observe for the first time electron diffraction from man made diffraction gratings of 100 nm periodicity. The high quality of diffraction and the ability to "pick" the periodicity allowed us to construct the first Mach-Zehnder electron interferometer using these gratings. Multiple approaches, including a prototype of our current interferometer and the combination of a grating with an electron bi-prism, were unsuccessful. Many stabilization issues must be overcome to observe electron interference fringes in the interferometer. Many experimental design ideas were used to reach proper stabilization requirements. The final interferometer design constructed was the only interferometer to obtain electron interference fringes. The theoretical model used to analyze the data is based on the path integral formalism. This calculates the amplitude associated with all classical paths through the experimental device. The sum of all amplitudes, the path integral, yields the resulting probability at the detection screen. We obtain good fits between our path integral calculations and experimental data. Alternate explanations of our data, such as the possibilities of Talbot Lau and classical Moiré interferometers are ruled out in favor of the Mach-Zehnder explanation. This type of interferometer could be used for future experiments. An experiment for which the fundamental quantum mechanical experiment has never been done; observing the dispersion-less nature of the Aharonov-Bohm Effect, may lend itself to the characteristics of this type of interferometer. Preliminary calculations have been performed to investigate the feasibility of using the grating technology to perform the required experiment.
Semitransparent mirrors are standard elements in light optics for splitting light beams or creating two versions of the same image. Such mirrors do not exist in electron optics, although they could be beneficial in existing techniques such as electron interferometry and holography and could enable alternative electron imaging and spectroscopy techniques. We propose a design for an electron beam splitter using the concept of quantum interaction-free measurement (IFM). The design combines an electron resonator with a weak phase grating. Fast switching gates allow electrons to enter and exit the resonator. While in the resonator, the phase grating transfers intensity from the direct beam into one of the weakly diffracted beams at each pass. To make the beam splitter an efficient two-port splitter, the intensity in all other diffracted beams is blocked by an aperture. The IFM principle minimizes the loss of total intensity by this aperture. We use a scattering matrix method to analyze the performance of the beam splitter, including the effects of inelastic scattering in the phase grating. This design can be generalized to beam splitters for not only electrons, but also photons, neutrons, atoms, and other quantum mechanical systems.
Feynman once asked physicists to build better electron microscopes to be able to watch biology at work. While electron microscopes can now provide atomic resolution, electron beam induced specimen damage precludes high resolution imaging of sensitive materials, such as single proteins or polymers. Here, we use simulations to show that an electron microscope based on a multi-pass measurement protocol enables imaging of single proteins, without averaging structures over multiple images. While we demonstrate the method for particular imaging targets, the approach is broadly applicable and is expected to improve resolution and sensitivity for a range of electron microscopy imaging modalities, including, for example, scanning and spectroscopic techniques. The approach implements a quantum mechanically optimal strategy which under idealized conditions can be considered interaction-free.
"Interaction-free measurements" (IFM) originate from the latest quantum interferometric technologies. The latest research of quantum optics demonstrates, by using the complementary wavelike and particlelike natures of photons, it is possible to make interaction-free measurements by which the presence of an object can be determined with no photons being absorbed. The paper introduces the concept of "Interaction-free Measurement" (IFM), the original Elitzur-Vaidman scheme, the "High Efficiency Interaction-free Measurement", the application of quantum Zeno effect and the improved scheme proposed by Kwiat et al. The EV scheme is implemented in a Mach-Zehnder interferometer. Theoretically this paper also draws a conclusion in IFM feasibility by analyzing the wave functions of photon at various locations in the interferometer.