Atoms and Energy

Part of the Undergraduate Lecture Notes in Physics book series (ULNP)


In this chapter, we look at the energy of electrons in an atom and determine how the quantum state of the atom changes over time. This leads us to introduce the energy operator, or Hamiltonian, and the Schrödinger equation that governs the behaviour of quantum systems. We show how light can interact with an atom, and as a demonstration of the quantum theory developed so far we explain how atomic clocks work.


energyEnergy frequencyFrequency phasePhase laserLaser photonsPhotons 
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Supplementary material (1012 kb)
Supplementary material 1: Spectral lines (zip 1011 KB) (1016 kb)
Supplementary material 2: The origin of spectral lines due to energy levels of the hydrogen atom (zip 1015 KB) (186 kb)
Supplementary material 3: Time evolution as a rotation of the state vector in the Bloch sphere (zip 186 KB) (2 mb)
Supplementary material 4: Working principle of the atomic clock (zip 2039 KB)


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.University of SheffieldSheffieldUK

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