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

Annalen der Physik

Molecular beams entwined with quantum theory: A bouquet for Max Planck

Dudley R. Herschbach

Published Feb 1, 2001• 0 citations
Publisher

Abstract

Abstract In an era when the fledgling quantum theory was “uncertain and even gave contradictory answers,” Otto Stern undertook to employ molecular beams to test directly fundamental aspects of the theory. During 1921‐1935, this led to five decisive experiments reviewed here, resulting in the discovery or demonstration of space quantization, de Broglie matter waves, anomalous magnetic moments of the proton and neutron, recoil of an atom on emission of a photon, and the limitation of scattering cross‐sections for molecular collisions imposed by the uncertainty principle.

DOI
10.1002/andp.200151301-215

Related papers

Otto Stern’s Molecular Beam Method and Its Impact on Quantum Physics

Břetislav Friedrich, H. Schmidt‐Böcking

Abstract Motivated by his interest in thermodynamics and the emerging quantum mechanics, Otto Stern (1888–1969) launched in 1919 his molecular beam method to examine the fundamental assumptions of theory that transpire in atomic, molecular, optical, and nuclear physics. Stern’s experimental endeavors at Frankfurt (1919–1922), Hamburg (1923–1933), and Pittsburgh (1933–1945) provided insights into the quantum world that were independent of spectroscopy and that concerned well-defined isolated systems, hitherto accessible only toGedankenexperiments. In this chapter we look at how Stern’s molecular beam research came about and review six of his seminal experiments along with their context and reception by the physics community: the Stern-Gerlach experiment; the three-stage Stern-Gerlach experiment; experimental evidence for de Broglie’s matter waves; measurements of the magnetic dipole moment of the proton and the deuteron; experimental demonstration of momentum transfer upon absorption or emission of a photon; the experimental verification of the Maxwell-Boltzmann velocity distribution via deflection of a molecular beam by gravity. Regarded as paragons of thoroughness and ingenuity, these experiments entail accurate transversal momentum measurements with resolution better than 0.1 atomic units. Some of these experiments would be taken up by others where Stern left off only decades later (matter-wave scattering or photon momentum transfer). We conclude by highlighting aspects of Stern’s legacy as reflected by the honors that have been bestowed upon him to date.

Springer eBooks•Jan 1, 2021•6 citations

Grating Diffraction of Molecular Beams: Present Day Implementations of Otto Stern’s Concept

Wieland Schöllkopf

Abstract When Otto Stern embarked on molecular-beam experiments in his new lab at Hamburg University a century ago, one of his interests was to demonstrate the wave-nature of atoms and molecules that had been predicted shortly before by Louis de Broglie. As the effects of diffraction and interference provide conclusive evidence for wave-type behavior, Otto Stern and his coworkers conceived two matter-wave diffraction experiments employing their innovative molecular-beam method. The first concept assumed the molecular ray to coherently scatter off a plane ruled grating at grazing incidence conditions, while the second one was based on the coherent scattering from a cleaved crystal surface. The latter concept allowed Stern and his associates to demonstrate the wave behavior of atoms and molecules and to validate de Broglie’s formula. The former experiment, however, fell short of providing evidence for diffraction of matter waves. It was not until 2007 that the grating diffraction experiment was retried with a modern molecular-beam apparatus. Fully resolved matter-wave diffraction patterns were observed, confirming the viability of Otto Stern’s experimental concept. The correct explanation of the experiment accounts for quantum reflection, another wave effect incompatible with the particle picture, which was not foreseen by Stern and his contemporaries.

Springer eBooks•Jan 1, 2021•1 citation

Historical Experiments and Theories

Şaki̇r Erkoç

The important discoveries and events that occurred in the development of quantum mechanics may be ordered as follows: Blackbody radiation formulated by Max Planck in 1901. Photoelectric effect interpreted by Albert Einstein in 1905. Model of the atom proposed by Ernest Rutherford in 1911. Quantum theory of atomic spectra developed by Niels Bohr in 1913. Photon–electron scattering experiments done by Arthor Holly Compton in 1922. Exclusion principle proposed by Wolfgang Pauli in 1925. Matter waves proposed by Prince Louis Victor de Broglie in 1925. Wave equation proposed by Erwin Shrödinger in 1926. Electron diffraction experiments done by Clinton Joseph Davisson and L.H. Germer in 1927. Uncertainty principle proposed by Werner Karl Heisenberg in 1927. Interpretation of the wave function done by Max Born in 1927. Relativistic wave equation proposed by Paul A. M. Dirac in 1928.

CRC Press eBooks•Jul 28, 2006•0 citations

Otto Stern and Wave-Particle Duality

Jan Peter Toennies

Abstract The contributions of Otto Stern to the discovery of wave-particle duality of matter particles predicted by de Broglie are reviewed. After a short introduction to the early matter-vs-wave ideas about light, the events are highlighted which lead to de Broglie’s idea that all particles, also massive particles, should exhibit wave behavior with a wavelength inversely proportional to their mass. The first confirming experimental evidence came for electrons from the diffraction experiments of Davisson and Germer and those of Thomson. The first demonstration for atoms, with three orders of magnitude smaller wave lengths, came from Otto Stern’s laboratory shortly afterwards in 1929 in a remarkabletour de forceexperiment. After Stern’s forced departure from Hamburg in 1933 it took more than 40 years to reach a similar level of experimental perfection as achieved then in Stern’s laboratory. Today He atom diffraction is a powerful tool for studying the atomic and electronic structure and dynamics of surfaces. With the advent of nanotechnology nanoscopic transmission gratings have led to many new applications of matter waves in chemistry and physics, which are illustrated with a few examples and described in more detail in the following chapters.

Springer eBooks•Jan 1, 2021•1 citation

Otto Stern’s Legacy in Quantum Optics: Matter Waves and Deflectometry

Stefan Gerlich, Yaakov Y. Fein, Armin Shayeghi +3 more

Abstract Otto Stern became famous for molecular beam physics, matter-wave research and the discovery of the electron spin, with his work guiding several generations of physicists and chemists. Here we discuss how his legacy has inspired the realization of universal interferometers, which prepare matter waves from atomic, molecular, cluster or eventually nanoparticle beams. Such universal interferometers have proven to be sensitive tools for quantum-assisted force measurements, building on Stern’s pioneering work on electric and magnetic deflectometry. The controlled shift and dephasing of interference fringes by external electric, magnetic or optical fields have been used to determine internal properties of a vast class of particles in a unified experimental framework.

Springer eBooks•Jan 1, 2021•2 citations

Otto Stern—An Involuntary Convert to Quantum Theory

Břetislav Friedrich

ABSTRACT The bulk of experiments and observations that lined the path to quantum mechanics amounted to a backlog of data in need of explanation. A notable exception was the Stern–Gerlach experiment (SGE) designed to test the predictions of the old quantum theory as embodied by the 1913–1916 Bohr–Sommerfeld–Debye atom model. After its initial triumphs, such as the explanation of the astrophysically observed spectrum of , this model was frowned upon in some quarters, mainly because of its ad hoc nature. Otto Stern (1888–1969)—and his close colleague and friend, Max von Laue (1879–1960)—even took a vow: “If this nonsense of Bohr should, in the end, prove to be right, we will quit physics.” Stern would go further yet and, in 1920, devise an experiment—the SGE—to disprove Bohr's model. However, contrary to Stern's expectations, the SGE ruled unequivocally in favor of the model and its amendments. Wolfgang Pauli (1900–1958) quipped: “That should convert even the non‐believer Stern.” And it did: Confronted with the outcome of the SGE, Stern noted in 1961: “I still have objections to the idea of beauty of quantum mechanics. But she is correct.” Ironically, the SGE would epitomize quantum mechanics as we know it: whether quantum measurement, state preparation, coherence, or entanglement—in addition to the quantization of angular momentum and its spatial projections—the SGE has it all. It now seems that the SGE may even impact future studies of the relationship of quantum theory to other pillars of physics, most notably, general relativity. The descendants of the SGE include transformative techniques for the study of the quantum properties of nuclear, atomic, molecular, and condensed‐matter systems, with magnetic resonance imaging being among the most widely used. Key Points Edward Pickering; Williamina Fleming; Pickering series; Bohr‐Sommerfeld‐Debye model of the atom; Otto Stern; Stern‐Gerlach experiment; Bohr magneton; Old Quantum Theory; Spin; nuclear magneton; magnetic dipole moment of the proton; matter‐wave duality; Quantum Mechanics.

Natural Sciences•Apr 1, 2026•0 citations
Abstract In an era when the fledgling quantum theory was “uncertain and even gave contradictory answers,” Otto Stern undertook to employ molecular beams to test directly fundamental aspects of the theory. During 1921‐1935, this led to five decisive experiments reviewed here, resulting in the discovery or demonstration of space quantization, de Broglie matter waves, anomalous magnetic moments of the proton and neutron, recoil of an atom on emission of a photon, and the limitation of scattering cross‐sections for molecular collisions imposed by the uncertainty principle.
Abstract Motivated by his interest in thermodynamics and the emerging quantum mechanics, Otto Stern (1888–1969) launched in 1919 his molecular beam method to examine the fundamental assumptions of theory that transpire in atomic, molecular, optical, and nuclear physics. Stern’s experimental endeavors at Frankfurt (1919–1922), Hamburg (1923–1933), and Pittsburgh (1933–1945) provided insights into the quantum world that were independent of spectroscopy and that concerned well-defined isolated systems, hitherto accessible only toGedankenexperiments. In this chapter we look at how Stern’s molecular beam research came about and review six of his seminal experiments along with their context and reception by the physics community: the Stern-Gerlach experiment; the three-stage Stern-Gerlach experiment; experimental evidence for de Broglie’s matter waves; measurements of the magnetic dipole moment of the proton and the deuteron; experimental demonstration of momentum transfer upon absorption or emission of a photon; the experimental verification of the Maxwell-Boltzmann velocity distribution via deflection of a molecular beam by gravity. Regarded as paragons of thoroughness and ingenuity, these experiments entail accurate transversal momentum measurements with resolution better than 0.1 atomic units. Some of these experiments would be taken up by others where Stern left off only decades later (matter-wave scattering or photon momentum transfer). We conclude by highlighting aspects of Stern’s legacy as reflected by the honors that have been bestowed upon him to date.
Abstract When Otto Stern embarked on molecular-beam experiments in his new lab at Hamburg University a century ago, one of his interests was to demonstrate the wave-nature of atoms and molecules that had been predicted shortly before by Louis de Broglie. As the effects of diffraction and interference provide conclusive evidence for wave-type behavior, Otto Stern and his coworkers conceived two matter-wave diffraction experiments employing their innovative molecular-beam method. The first concept assumed the molecular ray to coherently scatter off a plane ruled grating at grazing incidence conditions, while the second one was based on the coherent scattering from a cleaved crystal surface. The latter concept allowed Stern and his associates to demonstrate the wave behavior of atoms and molecules and to validate de Broglie’s formula. The former experiment, however, fell short of providing evidence for diffraction of matter waves. It was not until 2007 that the grating diffraction experiment was retried with a modern molecular-beam apparatus. Fully resolved matter-wave diffraction patterns were observed, confirming the viability of Otto Stern’s experimental concept. The correct explanation of the experiment accounts for quantum reflection, another wave effect incompatible with the particle picture, which was not foreseen by Stern and his contemporaries.
The important discoveries and events that occurred in the development of quantum mechanics may be ordered as follows: Blackbody radiation formulated by Max Planck in 1901. Photoelectric effect interpreted by Albert Einstein in 1905. Model of the atom proposed by Ernest Rutherford in 1911. Quantum theory of atomic spectra developed by Niels Bohr in 1913. Photon–electron scattering experiments done by Arthor Holly Compton in 1922. Exclusion principle proposed by Wolfgang Pauli in 1925. Matter waves proposed by Prince Louis Victor de Broglie in 1925. Wave equation proposed by Erwin Shrödinger in 1926. Electron diffraction experiments done by Clinton Joseph Davisson and L.H. Germer in 1927. Uncertainty principle proposed by Werner Karl Heisenberg in 1927. Interpretation of the wave function done by Max Born in 1927. Relativistic wave equation proposed by Paul A. M. Dirac in 1928.
Abstract The contributions of Otto Stern to the discovery of wave-particle duality of matter particles predicted by de Broglie are reviewed. After a short introduction to the early matter-vs-wave ideas about light, the events are highlighted which lead to de Broglie’s idea that all particles, also massive particles, should exhibit wave behavior with a wavelength inversely proportional to their mass. The first confirming experimental evidence came for electrons from the diffraction experiments of Davisson and Germer and those of Thomson. The first demonstration for atoms, with three orders of magnitude smaller wave lengths, came from Otto Stern’s laboratory shortly afterwards in 1929 in a remarkabletour de forceexperiment. After Stern’s forced departure from Hamburg in 1933 it took more than 40 years to reach a similar level of experimental perfection as achieved then in Stern’s laboratory. Today He atom diffraction is a powerful tool for studying the atomic and electronic structure and dynamics of surfaces. With the advent of nanotechnology nanoscopic transmission gratings have led to many new applications of matter waves in chemistry and physics, which are illustrated with a few examples and described in more detail in the following chapters.
Abstract Otto Stern became famous for molecular beam physics, matter-wave research and the discovery of the electron spin, with his work guiding several generations of physicists and chemists. Here we discuss how his legacy has inspired the realization of universal interferometers, which prepare matter waves from atomic, molecular, cluster or eventually nanoparticle beams. Such universal interferometers have proven to be sensitive tools for quantum-assisted force measurements, building on Stern’s pioneering work on electric and magnetic deflectometry. The controlled shift and dephasing of interference fringes by external electric, magnetic or optical fields have been used to determine internal properties of a vast class of particles in a unified experimental framework.
ABSTRACT The bulk of experiments and observations that lined the path to quantum mechanics amounted to a backlog of data in need of explanation. A notable exception was the Stern–Gerlach experiment (SGE) designed to test the predictions of the old quantum theory as embodied by the 1913–1916 Bohr–Sommerfeld–Debye atom model. After its initial triumphs, such as the explanation of the astrophysically observed spectrum of , this model was frowned upon in some quarters, mainly because of its ad hoc nature. Otto Stern (1888–1969)—and his close colleague and friend, Max von Laue (1879–1960)—even took a vow: “If this nonsense of Bohr should, in the end, prove to be right, we will quit physics.” Stern would go further yet and, in 1920, devise an experiment—the SGE—to disprove Bohr's model. However, contrary to Stern's expectations, the SGE ruled unequivocally in favor of the model and its amendments. Wolfgang Pauli (1900–1958) quipped: “That should convert even the non‐believer Stern.” And it did: Confronted with the outcome of the SGE, Stern noted in 1961: “I still have objections to the idea of beauty of quantum mechanics. But she is correct.” Ironically, the SGE would epitomize quantum mechanics as we know it: whether quantum measurement, state preparation, coherence, or entanglement—in addition to the quantization of angular momentum and its spatial projections—the SGE has it all. It now seems that the SGE may even impact future studies of the relationship of quantum theory to other pillars of physics, most notably, general relativity. The descendants of the SGE include transformative techniques for the study of the quantum properties of nuclear, atomic, molecular, and condensed‐matter systems, with magnetic resonance imaging being among the most widely used. Key Points Edward Pickering; Williamina Fleming; Pickering series; Bohr‐Sommerfeld‐Debye model of the atom; Otto Stern; Stern‐Gerlach experiment; Bohr magneton; Old Quantum Theory; Spin; nuclear magneton; magnetic dipole moment of the proton; matter‐wave duality; Quantum Mechanics.