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Simon Foner developed a sensitive vibrating-sample magnetometer. A magnetized specimen oscillates relative to pickup coils, producing a periodic change of magnetic flux and hence an induced voltage. Calibration converts that signal into a magnetic moment. Moving the specimen makes its contribution oscillatory, allowing it to be separated from many static background fields. The apparatus turns the geometry and frequency of mechanical motion into a reproducible magnetic measurement.^[ref]

Biography: news.mit.edu/2007/lincoln-labs-foner-82-and-sandholm-76

William Shockley developed the theory of semiconductor p-n junctions and junction transistors. Forward bias injects minority carriers across a junction; diffusion and recombination then determine how those carriers move through the neighboring material. In a transistor, a thin base allows much of the injected population to reach the collecting junction, making one electrical signal control another. The theory connects junction structure and carrier transport with quantitative current-voltage behavior.^[ref]

Identity and biography: www.nobelprize.org/prizes/physics/1956/shockley/biographical/?o=3510

Ernst Ising solved the one-dimensional nearest-neighbor version of the spin model now called the Ising model. For ferromagnetic coupling $J$ and zero external field, its correlations decay with separation as $⟨s_0{s}_r⟩=[\tanh (J/(k_{B}T)){]}^r$. At every positive temperature the factor has magnitude below one, so correlations vanish at arbitrarily large distance and there is no finite-temperature long-range ferromagnetic order in this model. The result makes the role of dimensionality and fluctuations concrete, rather than assuming that an ordering interaction automatically creates macroscopic order.^[ref]

Michel H. Devoret coauthored a 1985 measurement of macroscopic quantum tunnelling in a current-biased Josephson junction. At higher temperatures, escape from the zero-voltage state characterized the junction in a thermal regime. At low temperatures, the escape rate stopped depending on temperature and agreed with the predicted quantum escape rate using those independently determined parameters. The comparison supplied quantitative evidence for tunnelling of the collective circuit coordinate, rather than merely observing an unexplained low-temperature switching rate.^[ref]

Identity source: commons.wikimedia.org/wiki/File:Michel_H._Devoret,_French_American_physicist.jpg

A condensed matter physicist who coauthored the quantronium circuit experiment. The superconducting device combined microwave state manipulation with a separate pulsed measurement circuit, allowing coherent evolution and readout of an electrical qubit. It supplied an experimental connection between circuit design and the dynamics of a controllable quantum state.^[ref]

An experimental condensed matter physicist who coauthored coherent control of a superconducting electrical circuit. Microwave pulses programmed evolution between two circuit states, while a pulsed readout circuit measured the result. The device behaved as an artificial two-level system, making a fabricated circuit a controllable carrier of quantum information.^[ref]

Daniel Esteve coauthored the quantronium demonstration of coherent superconducting-circuit control. Its combination of programmable microwave evolution and pulsed readout made an electrical circuit a candidate carrier of quantum information.^[ref]

Identity source: iramis.cea.fr/en/spec/gq/membres-gq-en/

Cristian Urbina coauthored manipulation and readout of a superconducting electrical qubit. Microwave pulse sequences programmed its quantum state, while a separate pulsed subcircuit measured the outcome.^[ref]

Identity source: iramis.cea.fr/en/spec/gq/membres-gq-en/

Hugues Pothier coauthored the quantronium experiment, in which a superconducting tunnel-junction circuit acted as an artificial two-level system with programmable microwave-driven evolution and pulsed quantum measurement.^[ref]

Identity source: iramis.cea.fr/en/spec/gq/membres-gq-en/

Philippe Joyez coauthored coherent control of the quantronium qubit. The circuit separated microwave state manipulation from pulsed measurement, connecting superconducting-device design with controlled two-state quantum dynamics.^[ref]

Identity source: iramis.cea.fr/en/spec/gq/membres-gq-en/

Denis Vion coauthored the quantronium experiment: microwave pulses controlled the quantum state of a superconducting circuit behaving as a two-level system, with separate pulsed readout.^[ref]

Identity source: iramis.cea.fr/en/spec/gq/membres-gq-en/

Evangelista Torricelli interpreted the support of a Mercury column in terms of external atmospheric pressure. His 11 June 1644 letter to Michelangelo Ricci describes equal column heights in vessels with different upper spaces, testing whether the support came from outside the vessel. In modern hydrostatic pressure notation, $p_{\mathrm{atm}}-p_{\mathrm{top}}=\rho gh$, where $\rho$ is the liquid's density and $g$ is gravitational acceleration. When the upper pressure is small, the column height measures atmospheric pressure, as in a barometer. Comparing liquids of different densities explains why water requires a much taller column than Mercury.^[ref]

A physicist and mathematician associated here with Torricelli's law.^[ref]

Meng Cui and Changhuei Yang demonstrated digital optical phase conjugation through a multiple scattering sample. A charge-coupled device measured a transmitted light field by wave interference with a reference. A calibrated spatial light modulator then imposed the opposite spatial wave phase on the returning beam. Comparing this return with a zero-phase control showed recovery of the original optical mode. The method separated field measurement from playback and made finite sampling and phase-only control explicit limits on reconstruction.^[ref]

An optical physicist and coauthor of the digital optical phase conjugation experiment described there.^[ref]

An experimental physicist known for measurements of electron charge and the photoelectric effect. The Millikan photoelectric experiment describes the apparatus and stopping-voltage measurements behind his 1916 test.^[ref]

Otto Robert Frisch and Lise Meitner interpreted the barium found after uranium bombardment as evidence that a heavy atomic nucleus could divide into two large fragments. Their 1939 paper related the available energy to nuclear mass differences and the electrical repulsion of the fragments. This supplied a physical account of nuclear fission, connecting a chemical identification of the products with a new type of nuclear transformation and its large energy release.^[ref]

A physicist who worked with Lise Meitner on the interpretation of nuclear fission.^[ref]

A physicist who helped explain nuclear fission. Lise Meitner and Otto Robert Frisch interpreted the energy release associated with the chemical findings of Otto Hahn and Fritz Strassmann. Following these contributions together distinguishes the identification of reaction products from their physical explanation.^[ref]

A physicist associated with the Bohr model of the chemical atom. His 1922 Nobel Prize in Physics concerned atomic structure and radiation.^[ref][ref]

Max Planck introduced energy elements proportional to frequency, $ϵ=h\nu$, in his statistical treatment of thermal resonators. This led to a mean resonator energy $\overline{E}=h\nu /(e^{h\nu /(k_{B}T)}-1)$ and the corresponding black-body radiation spectrum, connecting entropy counting with measured radiation. For $h\nu \ll k_{B}T$, expanding the exponential gives $\overline{E}\approx k_{B}T$; at high frequency the denominator suppresses the energy exponentially. The energy-element argument was a step toward quantum theory, without yet being the later light-quantum account of a free photon.^[ref]

A physicist whose work on black-body radiation led to Planck's law and the use of the Planck constant. He received the 1918 Nobel Prize in Physics.^[ref]

Paul Dirac sought a relativistic quantum mechanics whose evolution equation remained first order in both time and spatial derivatives. A free-particle Hamiltonian $H=c\mathbf{\alpha }\cdot \mathbf{p}+\beta m{c}^2$ reproduces the relativistic relation $H^2=c^2{\mathbf{p}}^2+m^2{c}^4$ when its coefficient matrices satisfy suitable anticommutator identities. The required multi-component wave function incorporates electron spin within the relativistic dynamics. His 1928 paper used this construction to address the doubling of atomic states that earlier theories had treated by adding spin separately.^[ref]

A physicist who developed a relativistic theory of the electron. He shared the Nobel Prize in Physics in 1933 with Erwin Schrödinger.^[ref]

A physicist who developed wave mechanics. In 1926, Erwin Schrödinger made the energies of chemical atoms an eigenvalue problem, rather than prescribing a separate quantization rule for each classical orbit. He shared the Nobel Prize in Physics in 1933 with Paul Dirac.^[ref]

The Schrödinger equation turns a proposed Hamiltonian operator into predictions for a wavefunction and its evolution. Boundary conditions can select discrete energy eigenvalues, while quantum superposition makes their relative quantum phases observable through interference. The infinite square well gives a transparent worked example; a hydrogen atom supplies a physical application with a different potential energy.

The Davisson–Germer experiment gives a complementary experimental route into matter waves: an accelerated electron beam scattered from a nickel crystal produces direction-dependent collected electric current. Its apparatus and angular scans make the wave prediction testable. Interpreting a wavefunction as a probability amplitude also requires the Born rule; that statistical interpretation deserves its own history alongside Erwin Schrödinger's dynamics.